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Corel DVD MovieFactory is a video editing and DVD authoring software product for Microsoft Windows, initially made by Ulead Systems and subsequently by Corel. It creates and authors multimedia discs in HD DVD, Blu-ray, DVD Video and DVD Audio. It also creates and rips Audio CDs and MP3 CDs. DVD MovieFactory is commonly bundled with many of the modern Toshiba Satellite laptops. Official Japanese version is also known as MovieWriter.
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The Webby Awards (colloquially referred to as the Webbys) are awards for excellence on the Internet presented annually by the International Academy of Digital Arts and Sciences, a judging body composed of over three thousand industry experts and technology innovators. Categories include websites, advertising and media, online film and video, mobile sites and apps, and social. Two winners are selected in each category, one by members of The International Academy of Digital Arts and Sciences, and one by the public who cast their votes during Webby People's Voice voting. Each winner presents a five-word acceptance speech, a trademark of the annual awards show. In its early years, the award was hailed as the "Internet's highest honor" and was associated with the phrase "The Oscars of the Internet." == History == In its early years, the organization was one of several vying to be the premiere internet awards show. Both shows would compare themselves to the Oscars, as did media outlets such as The New York Times to Canada's Globe & Mail. The winners of the First Annual Webby Awards in 1995 were presented by John Brancato and Michael Ferris, writers for Columbia Pictures. It was held at the Hollywood Roosevelt Hotel. The televised Webby Awards were sponsored by the Academy of Web Design and Cool Site of the Day. The first Webby Awards were produced by Kay Dangaard at the Hollywood Roosevelt Hotel as a nod to the first site of the Academy of Motion Picture Arts and Sciences (Oscars). That first year, they were called "Webbie" Awards. The first "Site of the Year" winner was the pioneer webisodic serial The Spot. The modern Webby Awards were co-founded by Tiffany Shlain, a filmmaker, when she was hired by The Web Magazine to re-establish them, and were first held in San Francisco in 1997. They quickly became known for its requirement that winners give their acceptance speeches in five words. After this, the awards became more successful than the magazine and IDG closed the publication. Shlain and co-founder Maya Draisin Farrah continued to run The Webby Awards until 2004. The International Academy of Digital Arts and Sciences, which selects the winners of The Webby Awards, was established in 1998 by co-founders Tiffany Shlain, Spencer Ante and Maya Draisin. Members of the Academy include Kevin Spacey, Grimes, Questlove, Internet inventor Vint Cerf, Instagram's Head of Fashion Partnerships Eva Chen, comedian Jimmy Kimmel, Twitter founder Biz Stone, Vice Media co-founder and CEO Shane Smith, Tumblr's David Karp, Director of Harvard's Berkman Klein Center for Internet & Society Susan P. Crawford, Refinery29's Executive Creative Director Piera Gelardi, and CEO and co-founder of Gimlet Media Alex Blumberg. The Webby Awards is owned and operated by the Webby Media Group, a division of Recognition Media, which also owns and produces the Lovie Awards in Europe and Netted by the Webbys, a daily email publication launched in 2009. David-Michel Davies, CEO of Webby Media Group, current Executive Director of the Webby Awards and co-founder of Internet Week New York, was named Executive Director of the Webby Awards in 2005. In 2009, the 13th Annual Webby Awards received nearly 10,000 entries from all 50 US states and over 60 countries. That same year, more than 500,000 votes were cast in The Webby People's Voice Awards. In 2012, the 16th Annual Webby awards received 1.5 million votes from more than 200 countries for the People's Voice awards. In 2015, the 19th Annual Webby Awards received nearly 13,000 entries from all 50 U.S. states and over 60 countries worldwide. == Nomination process == The 2000 awards began the transition to nominee submissions. Previously, nominees had been selected by an internal committee. As early as 2017, organizations wanting to nominate themselves were charged $395 for a single entry. An "ad campaign entry" would cost $595. By 2024, those fees had risen to $495 and $675, respectively. Executive Academy Members with category-specific expertise evaluate the shortlisted entries based on the appropriate Website, Advertising & Media, Online Film & Video, Mobile Sites & Apps, and Social category criteria, and cast ballots to determine Webby Honorees, Nominees and Webby Winners. Deloitte provides vote tabulation consulting for the Webby Awards. In addition to the award given in each category by the International Academy of Digital Arts and Sciences, another winner is selected in each category as determined by the general public during People's Voice voting. Winners of both the Academy-selected and People's Voice-selected awards are invited to the Webbys. == Awards granted == The Webby Awards are presented in over a hundred categories among all four types of entries. A website can be entered in multiple categories and receive multiple awards. In each category, two awards are handed out: a Webby Award selected by The International Academy of Digital Arts and Sciences, and a People's Voice Award selected by the general public. == Ceremony == Between 2005 and 2019, the Webby Awards were presented in New York City. Many of the ceremony hosts are comedians and comedic actors. Comedian Rob Corddry hosted the ceremony from 2005 to 2007. Seth Meyers of Saturday Night Live hosted in 2008 and 2009, B.J. Novak of the sitcom The Office in 2010, and Lisa Kudrow in 2011. Comedian, actor, and writer Patton Oswalt hosted from 2012 to 2014. Comedian Hannibal Buress hosted in 2015. The Webbys are famous for limiting recipients to five-word speeches, which are often humorous, although some exceed the limit. In 2005 when accepting his Lifetime Achievement Award, former Vice President Al Gore's speech was "Please don't recount this vote." He was introduced by Vint Cerf who used the same format to state, "We all invented the Internet." In 2013, the creator of the Graphics Interchange Format (GIF), Steve Wilhite, accepted his Webby and delivered his now famous five-word speech, "It's pronounced 'Jif' not 'Gif'." == Criticism == The Webbys have been criticized for their pay-to-enter and pay-to-attend policy (winners and nominees also have to pay to attend the award ceremony), and thus for not taking most websites into consideration before distributing their awards. Gawker, its Valleywag column, and others, have called the awards a scam, with Valleywag saying, "...somewhere along the way, the organizers figured out that this goofy charade could be milked for profit." In response, Webby Awards executive director David-Michel Davies told the Wall Street Journal that entry fees "provide the best and most sustainable model for ensuring that our judging process remains consistent and rigorous and is not dependent on things like sponsorships that can fluctuate from year to year." == Anthem Awards == In 2021, the Webby organization started a new line of awards, the Anthem Awards, to honor the purpose and mission-driven work of people, companies and organizations worldwide. The finalists and winners are selected by the International Academy of Digital Arts and Sciences.
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Nitro Zeus is the project name for a well funded comprehensive cyber attack plan created as a mitigation strategy after the Stuxnet malware campaign and its aftermath. Unlike Stuxnet, that was loaded onto a system after the design phase to affect its proper operation, Nitro Zeus's objectives are built into a system during the design phase unbeknownst to the system users. This built-in feature allows a more assured and effective cyber attack against the system's users. The information about its existence was raised during research and interviews carried out by Alex Gibney for his Zero Days documentary film. The proposed long term widespread infiltration of major Iranian systems would disrupt and degrade communications, power grid, and other vital systems as desired by the cyber attackers. This was to be achieved by electronic implants in Iranian computer networks. The project was seen as one pathway in alternatives to full-scale war.
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CSS HTML Validator (previously named CSE HTML Validator) is an HTML editor and CSS editor for Microsoft Windows (and Linux and other Unix-like operating systems when used with Wine) that helps web developers create syntactically correct and accessible HTML/HTML5, XHTML, and CSS documents by locating errors, potential problems like browser compatibility issues, and common mistakes. It is also able to check links, check spelling, suggest improvements, alert developers to deprecated, obsolete, or proprietary tags, attributes, and CSS properties, and find issues that can affect search engine optimization. CSS HTML Validator is developed, marketed, and sold by AI Internet Solutions LLC located in the United States. The first version of CSS HTML Validator was released in 1997 for Windows 95. The current version is 2026/v26.02 (as of January 9, 2026) and is for Windows 10 and above, including Windows 11. A native macOS and Linux command-line console tool (called htmlval) became available with version 23. There are currently three main editions of CSS HTML Validator — Pro/Professional, Home/Standard, and Lite. The Enterprise edition was discontinued in 2025/v25. While the application is generally a commercial product (except for the Lite edition), a free version of the Home edition is available for personal/educational, non-commercial use. A free limited version of the htmlval command-line console tool for macOS and Linux is also available. == Features == CSS HTML Validator includes an HTML editor, validator for HTML, XHTML, htmx, polyglot markup, CSS, PHP and JavaScript (using JSLint or JSHint), link checker (to find dead and broken links), spell checker, accessibility checker, and search engine optimization (SEO) checker. An integrated web browser allows developers to browse the web while the pages are automatically validated. Because documents are checked locally and not uploaded over the Internet to a server in order to be checked, validations are performed relatively quickly, and security and privacy are increased. A custom scripting language called TNPL, included in the Pro and Enterprise editions, can be used to customize validations by adding, eliminating, or changing validator messages. TNPL can also be used to integrate customized validation checks to meet the unique requirements of an individual or entity. A Batch Wizard tool, included in the Pro and Enterprise editions, can check entire Web sites, parts of Web sites, or a list of local web documents. The Batch Wizard generates reports in standard HTML or XML format. The reports can be viewed using a normal web browser. The accessibility checker includes support for Section 508 Amendment to the Rehabilitation Act of 1973 and Web Content Accessibility Guidelines (both WCAG 1.0 and WCAG 2.0/2.1/2.2). Using a version of HTML Tidy with HTML5 support and the Pretty Print & Fix Tool, CSS HTML Validator can automatically fix some common problems with HTML and XHTML documents. However, some problems cannot be fixed (or fixed correctly) with automated tools and require manual review and repair. == Version history == Validation of polyglot markup was added in version 12, and mobile development support (for HTML and CSS) was added in version 14 and improved in version 15. Version 15 added built-in syntax checking for JSON and HTML5 cache manifest files. Version 16 added JavaScript linting using JSHint, a static code analysis tool for checking JavaScript, but also continues to support JSLint. Version 17 added support for the Accelerated Mobile Pages Project, which is a type of HTML optimized for mobile web browsing, and support for live DOM validation using Google Chrome CSS HTML Validator 2018/v18 renames the software from CSE HTML Validator to CSS HTML Validator and includes updated HTML5 and CSS support. Version 18 also added a new "By Message" report in the Batch Wizard and dropped support for Windows Vista and below. CSS HTML Validator 2019/v19 includes updated HTML and CSS support, adds WCAG 2.1 support, improves support when running under Wine (software), and is a native 64-bit application (previously releases were 32-bit). CSS HTML Validator 2020/v20, first released in January 2020, includes HTML, CSS, accessibility, and other updates, including improved support for the Accelerated Mobile Pages Project. Also, beginning with version 20, the Standard edition was renamed to the Home edition. CSS HTML Validator 2021/v21, first released in January 2021, includes further HTML, CSS, accessibility, and other updates. CSS HTML Validator 2022/v22, released in January 2022, includes improvements and updates to keep the program up-to-date, a new Microsoft Edge WebView2 rendering engine for the integrated web browser, and three new dark themes. Later updates to version 22 added support for checking JSON Lines and NDJSON documents. CSS HTML Validator 2023/v23, released in January 2023, includes more improvements and updates to keep the program up-to-date. The new release also introduced new command-line macOS and Linux ports of the core validation engine, called htmlval for Mac and Linux. Official support for Windows 7, 8, and 8.1 was dropped in the 2023/v23 version. CSS HTML Validator 2024/v24, released in January 2024, includes updates and improvements. It also adds support for htmx. CSS HTML Validator 2025/v25, released in December 2024, includes further updates and improvements for 2025. Version 25 discontinues the Enterprise edition, moving Enterprise functionality to the Pro edition. CSS HTML Validator 2026/v26, released in January 2026, includes updated support for HTML and CSS. An online edition based on CSS HTML Validator Pro that can check documents via file upload, URL, or snippets (direct text input) was discontinued May 2017 in favor of the desktop version for Microsoft Windows. == Purpose of validation == The purpose of validation and computerized checking of HTML, XHTML, and CSS documents is to help make sure that the documents are syntactically correct and problem-free. Checked HTML, XHTML, and CSS documents are more likely to: be more accessible for people with disabilities (such as blindness), as well as all users in general render faster (user agents don't have to "figure out" and decipher bad syntax) render as intended and with fewer problems on a variety of user agents, including mobile devices cause browsers and user agents to build a more consistent Document Object Model, which is important for CSS and JavaScript be forward-compatible with future versions of user agents and browsers ("future-proof") be compatible with current and future HTML, XHTML, and CSS specifications cause fewer problems for visitors and web indexing not contain dead, broken, or rotting links While automated checking tools are helpful for website development and continued maintenance, they cannot guarantee that a document will display (render) and behave as intended in all browsers. Developers should always test documents in a variety of browsers (including mobile browsers) to locate problems that cannot be detected with a computerized checking tool. == Differences from other HTML validators == CSS HTML Validator is an offline desktop app for Microsoft Windows and a native macOS and Linux command-line console tool that does not require an Internet connection. The offline nature of CSS HTML Validator is in contrast to online web-based services. CSS HTML Validator primarily works offline (except for link checking when it must go online), which has speed and privacy benefits compared to web-based solutions and services like the W3C Markup Validation Service. However, the user must keep the software updated unlike web-based solutions which are typically kept updated by the solution provider. CSS HTML Validator checks HTML/XHTML syntax, CSS, links, spelling, accessibility, JavaScript, SEO, and PHP with one pass, while DTD-based validators are more limited and cannot check HTML5. CSS HTML Validator includes a built-in scripting language (called TNPL) which allows for a high degree of customization via scripting and "user functions". This allows developers to add custom (specialized) validation checks and messages. CSS HTML Validator includes a DTD-based validator which can optionally be used for checking DTD-based versions of HTML (versions prior to HTML5), however one of CSS HTML Validator's primary differences is that its custom validation engine can perform more checks on a document than a DTD-based validator can. This is because DTD-based validators are limited to checking only what can be specified in a Document Type Definition. == Integration == CSS HTML Validator integrates with other third-party software like those listed below. This allows validation using CSS HTML Validator from within the third-party program. EmEditor - includes a special Lite edition build of CSS HTML Validator for built-in checking of HTML and CSS Blumentals Software - several Blumentals software products integrate with CSS H
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Data annotation is the process of labeling or tagging relevant metadata within a dataset to enable machines to interpret the data accurately. The dataset can take various forms, including images, audio files, video footage, or text. == Applications == Data is a fundamental component in the development of artificial intelligence (AI). Training AI models, particularly in computer vision and natural language processing, requires large volumes of annotated data. Proper annotation ensures that machine learning algorithms can recognize patterns and make accurate predictions. Common types of data annotation include classification, bounding boxes, semantic segmentation, and keypoint annotation. Data annotation is used in AI-driven fields, including healthcare, autonomous vehicles, retail, security, and entertainment. By accurately labeling data, machine learning models can perform complex tasks such as object detection, sentiment analysis, and speech recognition with greater precision. This growing demand has led to the emergence of specialized sectors and platforms dedicated to AI training and human-in-the-loop workflows, which often utilize Reinforcement Learning from Human Feedback (RLHF) to refine model behavior. == In computer vision == === Image classification === Image classification, also known as image categorization, involves assigning predefined labels to images. Machine learning algorithms trained on classified images can later recognize objects and differentiate between categories. For instance, an AI model trained to recognize furniture styles can distinguish between Georgian and Rococo armchairs. === Semantic segmentation === Semantic segmentation assigns each pixel in an image to a specific class, such as trees, vehicles, humans, or buildings. This type of annotation enables machine learning models to differentiate objects by grouping similar pixels, allowing for a detailed understanding of an image. === Bounding boxes === Bounding box annotation involves drawing rectangular boxes around objects in an image. This technique is commonly used in autonomous driving, security surveillance, and retail analytics to detect and classify objects such as pedestrians, vehicles, and products on store shelves. === 3D cuboids === 3D cuboid annotation enhances traditional bounding boxes by adding depth, enabling models to predict an object's spatial orientation, movement, and size. This method is particularly useful for autonomous vehicles and robotics, where understanding object dimensions and depth is critical. === Polygonal annotation === For objects with irregular shapes, such as curved or multi-sided items, polygonal annotation provides more precise labeling than bounding boxes. This technique is often used in applications that require detailed object recognition, such as medical imaging or aerial mapping. === Keypoint annotation === Keypoint annotation marks specific points on an object, such as facial landmarks or body joints, to enable tracking and motion analysis. This method is widely used in facial recognition, emotion detection, sports analytics, and augmented reality applications.
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End-to-end encryption (E2EE) is a method of implementing a secure communication system where only the sender and intended recipient can read the messages. No one else, including the system provider, telecom providers, Internet providers or malicious actors, can access the cryptographic keys needed to read or send messages. End-to-end encryption prevents data from being read or secretly modified, except by the sender and intended recipients. In many applications, messages are relayed from a sender to some recipients by a service provider. In an E2EE-enabled service, messages are encrypted on the sender's device such that no third party, including the service provider, has the means to decrypt them. The recipients retrieve encrypted messages and decrypt them independently on their own devices. Since third parties cannot decrypt the data being communicated or stored, services with E2EE are better at protecting user data from data breaches and espionage. Computer security experts, digital freedom organizations, and human rights activists advocate for the use of E2EE due to its security and privacy benefits, including its ability to resist mass surveillance. Popular messaging apps like WhatsApp, iMessage, Facebook Messenger, and Signal use end-to-end encryption for chat messages, with some also supporting E2EE of voice and video calls. As of May 2025, WhatsApp is the most widely used E2EE messaging service, with over 3 billion users. Meanwhile, Signal with an estimated 70 million users, is regarded as the current gold standard in secure messaging by cryptographers, protestors, and journalists. Since end-to-end encrypted services cannot offer decrypted messages in response to government requests, the proliferation of E2EE has been met with controversy. Around the world, governments, law enforcement agencies, and child protection groups have expressed concerns over its impact on criminal investigations. As of 2025, some governments have successfully passed legislation targeting E2EE, such as Australia's Telecommunications and Other Legislation Amendment Act (2018) and the Online Safety Act (2023) in the UK. Other attempts at restricting E2EE include the EARN IT Act in the US and the Child Sexual Abuse Regulation in the EU.[1] Nevertheless, some government bodies such as the UK's Information Commissioner's Office and the US's Cybersecurity and Infrastructure Security Agency (CISA) have argued for the use of E2EE, with Jeff Greene of the CISA advising that "encryption is your friend" following the discovery of the Salt Typhoon espionage campaign in 2024. == Definitions == End-to-end encryption is a means of ensuring the security of communications in applications like secure messaging. Under E2EE, messages are encrypted on the sender's device such that they can be decoded only by the final recipient's device. In many non-E2EE messaging systems, including email and many chat platforms, messages pass through intermediaries and are stored by a third party service provider, from which they are retrieved by the recipient. Even if messages are encrypted, they are only encrypted 'in transit', and are thus accessible by the service provider. Server-side disk encryption is also distinct from E2EE because it does not prevent the service provider from viewing the information, as they have the encryption keys and can simply decrypt it. The term "end-to-end encryption" originally only meant that the communication is never decrypted during its transport from the sender to the receiver. For example, around 2003, E2EE was proposed as an additional layer of encryption for GSM or TETRA, in addition to the existing radio encryption protecting the communication between the mobile device and the network infrastructure. This has been standardized by SFPG for TETRA. Note that in TETRA, the keys are generated by a Key Management Centre (KMC) or a Key Management Facility (KMF), not by the communicating users. Later, around 2014, the meaning of "end-to-end encryption" started to evolve when WhatsApp encrypted a portion of its network, requiring that not only the communication stays encrypted during transport, but also that the provider of the communication service is not able to decrypt the communications—maliciously or when requested by law enforcement agencies. Similarly, messages must be undecryptable in transit by attackers through man-in-the-middle attacks. This new meaning is now the widely accepted one. == Motivations == The lack of end-to-end encryption can allow service providers to easily provide search and other features, or to scan for illegal and unacceptable content. However, it also means that content can be read by anyone who has access to the data stored by the service provider, by design or via a backdoor. This can be a concern in many cases where privacy is important, such as in governmental and military communications, financial transactions, and when sensitive information such as health and biometric data are sent. If this content were shared without E2EE, a malicious actor or adversarial government could obtain it through unauthorized access or subpoenas targeted at the service provider. E2EE alone does not guarantee privacy or security. For example, the data may be held unencrypted on the user's own device or accessed through their own app if their credentials are compromised. == Modern implementations == === Messaging === In May 2026, Meta ended support for end-to-end encryption (E2EE) on Instagram, reversing a previous commitment to expand the technology across its messaging services. The company justified the move as a measure to mitigate fraudulent activity and facilitate the detection of harmful content. The decision highlighted a conflict between digital privacy and online safety; while child protection organizations supported the change to better identify predatory behavior, privacy advocates argued that removing E2EE compromises user security. As of 2025, messaging apps like Signal and WhatsApp are designed to exclusively use end-to-end encryption. Both Signal and WhatsApp use the Signal Protocol. Other messaging apps and protocols that support end-to-end encryption include Facebook Messenger, iMessage, Telegram, Matrix, and Keybase. Although Telegram supports end-to-end encryption, it has been criticized for not enabling it by default, instead supporting E2EE through opt-in "secret chats". As of 2020, Telegram did not support E2EE for group chats and no E2EE on its desktop clients. In 2022, after controversy over the use of Facebook Messenger messages in an abortion lawsuit in Nebraska, Facebook added support for end-to-end encryption in the Messenger app. Writing for Wired, technologist Albert Fox Cahn criticized Messenger's approach to end-to-end encryption, which required the user to opt into E2EE for each conversation and split the message thread into two chats which were easy for users to confuse. In December 2023, Facebook announced plans to enable end-to-end encryption by default despite pressure from British law enforcement agencies. As of 2016, many server-based communications systems did not include end-to-end encryption. These systems can only guarantee the protection of communications between clients and servers, meaning that users have to trust the third parties who are running the servers with the sensitive content. End-to-end encryption is regarded as safer because it reduces the number of parties who might be able to interfere or break the encryption. In the case of instant messaging, users may use a third-party client or plugin to implement an end-to-end encryption scheme over an otherwise non-E2EE protocol. === Audio and video conferencing === Signal and WhatsApp use end-to-end encryption for audio and video calls. Since 2020, Signal has also supported end-to-encrypted video calls. In 2024, Discord added end-to-end encryption for audio and video calls, voice channels, and certain live streams. However, they had no plans to implement E2EE for messages. In 2020, after acquiring Keybase, Zoom announced end-to-end encryption would be limited to paid accounts. Following criticism from human rights advocates, Zoom extended the feature to all users with accounts. In 2021, Zoom settled an $85M class action lawsuit over past misrepresentation about end-to-end encryption. The FTC confirmed Zoom previously retained access to meeting keys. === Other uses === Some encrypted backup and file sharing services provide client-side encryption. Nextcloud and MEGA, offer end-to-end encryption of shared files. The term "end-to-end encryption" is sometimes incorrectly used to describe client-side encryption. Some non-E2EE systems, such as Lavabit and Hushmail, have described themselves as offering "end-to-end" encryption when they did not. == Law enforcement and regulation == In 2022, Facebook Messenger came under scrutiny because the messages between a mother and daughter in Nebraska were used to seek criminal charges in an abortion-rel
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Attention inequality is the inequality of distribution of attention across users on social networks, people in general, and for scientific papers. Yun Family Foundation introduced "Attention Inequality Coefficient" as a measure of inequality in attention and arguments it by the close interconnection with wealth inequality. == Relationship to economic inequality == Attention inequality is related to economic inequality since attention is an economically scarce good. The same measures and concepts as in classical economy can be applied for attention economy. The relationship develops also beyond the conceptual level—considering the AIDA process, attention is the prerequisite for real monetary income on the Internet. On data of 2018, a significant relationship between likes and comments on Facebook to donations is proven for non-profit organizations. == Attention economy == The attention economy refers to the practice of maximizing the attention users give to a product for advertising-related reasons. Attention economy remains one of the most common forms of advertising, and has been steadily increasing thanks to new technologies such as television, internet and social media. It is one of the most widely-used approaches to economy for its effectiveness for maximising the noticeability of a certain product. == Attention inequality in social media == In social media, attention inequality refers to the unequal distribution of users' attention on social media platforms. This means that instead of an equal distribution of attention, fewer sources receive a disproportionate share of attention, leaving many unnoticed. This phenomenon is possibly the result of social media algorithms, which are commonly designed to drive maximum engagement. This phenomenon is a large factor in the polarization and creation of echo-chambers. Social media algorithms tend to note content that is already performing well and display it to more users, while content that is equally engaging or well-made is not recommended to users. Posts that trigger strong emotions usually out-perform more "uncontroversial" content. When many users interact with the post, it signals the algorithm that the specific post drives engagement. The algorithm then tends to recommend that type of content to an exponential number of people, potentially outperforming "un-emotional" content. These factors, when combined, tend to create an unequal social media environment. == Attention inequality in science == According to a recent 2025 study about research inequality among scientists published in Information Processing and Management, scientific discourse is restricted to a small group of connected scientists, and is frequently not an accurate representation of the whole scientific community. Using citation-network analysis in the fields of nanoscience and chemical physics, the study claims that a group of connected scientists has a significant notability in the scientific community. The calculated connection strength between these scientists is estimated to be about 4.5, the study also says that these authors cite each other four times more often than would be predicted in a random network, whereas ordinary scientists that exist outside of this group only reach an estimated connection strength of 0.9. The study findings suggest that that scientific attention is not distributed by merit, but rather by the connectedness of the scientists involved in the research. == Extent == As data of 2008 shows, 50% of the attention is concentrated on approximately 0.2% of all hostnames, and 80% on 5% of hostnames. The Gini coefficient of attention distribution lay in 2008 at over 0.921 for such commercial domains names as ac.jp and at 0.985 for .org-domains. The Gini coefficient was measured on Twitter in 2016 for the number of followers as 0.9412, for the number of mentions as 0.9133, and for the number of retweets as 0.9034. For comparison, the world's income Gini coefficient was 0.68 in 2005 and 0.904 in 2018. More than 96% of all followers, 93% of the retweets, and 93% of all mentions are owned by 20% of Twitter. == Causes == At least for scientific papers, today's consensus states that inequality is unexplainable by variations of quality and individual talent. The Matthew effect plays a significant role in the emergence of attention inequality—those who already enjoy large amounts of attention get even more attention, and those who do not lose even more. Ranking algorithms based on relevance to the user have been found to alleviate the inequality of the number of posts across topics.
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SitePal is a speaking avatar platform for small and medium-sized businesses developed by Oddcast. SitePal allows users to deploy "virtual employees" on websites that can welcome visitors, guide them around the site and answer questions. The use of SitePal on commercial websites has been controversial because many visitors report finding them annoying. Some research has shown that they can increase sales in comparison to using static photographs. == Development == The technology used was the result of more than 4 years of research at Stanford University. The research was based on a literature review and other previous work in the field of artificial intelligence research. The SitePal AI option uses the AIML programming language, which is partially editable by users. This allows web designers to simulate normal human conversation by using keywords or key phrases that the bot can respond to. == Features == The company provides web designers with options to customize the chosen avatar. A large selection of faces, clothing, hair, backgrounds, voices and other details are available. If a web designer wants to use a particular face, Sitepal can create one from a photo. Thus, a mascot or a known face can be simulated. == Speech == Sitepal avatars talk through text-to-speech (tts) software. A short paragraph can be written (up to 900 characters) and the text-to-speech engine will compile the actual speech, which can be reproduced and edited. The tts engine is not perfect, but it comes close to actual speech and is easy to understand. Tts can be further enhanced by some commands, like /laugh and /loud which make the avatar laugh or talk loud. Even pronunciation is possible. The web designer can record and upload his or her own audio messages. Alternatively Sitepal offers professional voice acting service at extra cost. == User interaction == The company provides 5 options for visitor interaction: No interaction. The avatar simply says a pre-fixed message. FAQ mode. Questions can be configured, which are clickable and the user can hear the answer. Lead mode. The avatar prompts the user to type his email and short message, so it can be sent to the webmaster (usually used on a "contact us" page) Chatbot mode. The avatar greets the user, and he can type his questions and have a conversation with the bot. With predetermined replies, this can work as an FAQ as well. API customization. Experienced programmers can make their avatar interact with their website, making it talk when the user clicks on a link or when other triggers occur. Even dual avatar conversations can be created, like a talk show. == Posting options == The company provides five options for posting the avatar: Embed in webpage (via javascript) Embed in HTML Send by email Publish to eBay Embed in Flash == Criticism == Early reviews, such as one by Troy Dreier published in PC World in 2002 were positive and described SitePal as: "an engagingly simple and personal tool, and the price is reasonable for what it adds to a site". Although Dreier did note that the program had "bugs that suggested it hadn't been tested thoroughly". In more recent years, reaction to SitePal has been much more negative with reviews such as Tom Spring writing in a PC World review citing SitePal ads and described his reaction as "Not so nice". Paul Bissex, writing in E-Scribe News described SitePal as "heinous... and embarrassing if anyone is within earshot...they creep me out" == Research on effectiveness == In one single-website research project Anita Campbell had half the visitors to Small Business Trends see a SitePal and the other half see just a static photograph. Over 11,000 visitors the SitePal avatar improved sign-up for a newsletter 144% over the control condition.
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Cognitive philology is the science that studies written and oral texts as the product of human mental processes. Studies in cognitive philology compare documentary evidence emerging from textual investigations with results of experimental research, especially in the fields of cognitive and ecological psychology, neurosciences and artificial intelligence. "The point is not the text, but the mind that made it". Cognitive Philology aims to foster communication between literary, textual, philological disciplines on the one hand and researches across the whole range of the cognitive, evolutionary, ecological and human sciences on the other. Cognitive philology: investigates transmission of oral and written text, and categorization processes which lead to classification of knowledge, mostly relying on the information theory; studies how narratives emerge in so called natural conversation and selective process which lead to the rise of literary standards for storytelling, mostly relying on embodied semantics; explores the evolutive and evolutionary role played by rhythm and metre in human ontogenetic and phylogenetic development and the pertinence of the semantic association during processing of cognitive maps; Provides the scientific ground for multimedia critical editions of literary texts. Among the founding thinkers and noteworthy scholars devoted to such investigations are: Alan Richardson: Studies Theory of Mind in early-modern and contemporary literature. Anatole Pierre Fuksas Benoît de Cornulier David Herman: Professor of English at North Carolina State University and an adjunct professor of linguistics at Duke University. He is the author of "Universal Grammar and Narrative Form" and the editor of "Narratologies: New Perspectives on Narrative Analysis". Domenico Fiormonte François Recanati Gilles Fauconnier, a professor in Cognitive science at the University of California, San Diego. He was one of the founders of cognitive linguistics in the 1970s through his work on pragmatic scales and mental spaces. His research explores the areas of conceptual integration and compressions of conceptual mappings in terms of the emergent structure in language. Julián Santano Moreno Luca Nobile Manfred Jahn in Germany Mark Turner Paolo Canettieri
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Digital signage is a segment of electronic signage that uses digital display technologies to present multimedia content in both public and private environments. Content may include video, images, text, or interactive media and is typically displayed for purposes such as advertising, information dissemination, branding, or entertainment. Digital signage systems can be either networked or standalone. Networked systems are managed through centralized content management systems (CMS), often cloud-based, enabling remote updates, scheduling, real-time data integration, and dynamic content delivery. These systems may also incorporate audience analytics, IoT sensors, or AI-driven personalization. Standalone systems, by contrast, operate without a network connection. They rely on local media playback via USB drives, SD cards, or internal storage. These solutions are simpler and suitable for locations where connectivity is limited or content changes infrequently. == Applications of digital signage == Digital signage is widely used in transportation hubs, retail stores, restaurants, corporate buildings, hotels, educational institutions, healthcare facilities, and public spaces. One prominent application of digital signage is Digital Out-of-Home (DOOH) advertising, which leverages digital signage displays in public spaces to deliver targeted advertisements to people outside of their homes. DOOH has become a significant segment of digital signage, providing advertisers with a dynamic and contextually relevant way to engage with audiences. == Components == === Hardware components === Digital signage hardware includes the physical equipment used to show multimedia content in public and private spaces. ==== Display devices ==== Display devices are the most prominent components of a digital signage system, serving as the primary medium for presenting content. Display devices come in various technologies, such as LCD, LED, and OLED formats, each offering different advantages in terms of clarity, color reproduction, and energy efficiency. In addition to flat-panel displays, projectors are also commonly used in digital signage, particularly in large-scale settings. Projectors can cast large-format visuals onto walls, screens, or other surfaces, providing flexibility in display size and positioning. Screen sizes vary widely to suit different applications. Smaller panels are often used in kiosks and point-of-sale systems, while larger displays, such as video walls and projection surfaces, are deployed in venues like stadiums, auditoriums, and other public spaces. Many digital signage displays are also equipped with touchscreen capabilities, allowing for interactive applications. These interactive displays are commonly used in information kiosks, wayfinding systems, and self-service applications. ==== Playback devices ==== Playback devices are specialized hardware components that manage the storage, processing, and transmission of multimedia content to digital signage displays and projectors. They serve as the crucial link between the content management system (CMS) and the visual output, ensuring seamless playback of static images, video files, animated graphics, and real-time content, such as news feeds. Playback devices can be standalone units or integrated into display hardware using System-on-Chip (SoC) technology. The latter reduces hardware complexity and installation time, making the system more efficient. These devices support remote or local content updates, allowing digital signage operators to manage networks effectively. Content can be updated via cloud-based platforms for centralized control or through direct interfaces on-site, depending on the system's configuration and deployment requirements. ==== Mounting systems ==== Mounting systems provide structural support for digital signage displays, enabling deployment across diverse environments. Typical configurations include wall mounts, ceiling mounts, and floor stands each engineered to meet specific spatial and functional requirements. === Software components === Digital signage software is responsible for content creation, scheduling, and management. It enables users to manage and distribute content to one or more playback devices. ==== Software compatibility ==== Digital signage software supports various operating systems, including Android, Windows, Linux, iOS, tvOS, webOS, Tizen, ChromeOS, macOS, and others. This allows customers to choose the hardware and software solution that best suits their digital signage needs. == Interactivity == Interactivity in digital signage allows users to interact directly with displays using input methods like touch, gestures, voice, or proximity sensors. This feature enables real-time responses and personalized content, improving the user experience. Interactive digital signage is commonly used in places like retail, transportation, education, and public spaces to create engaging and informative interactions. Additionally, self-service kiosks are often integrated into interactive signage solutions, allowing users to perform tasks such as ordering products, checking in for flights, accessing information, or making payments. These kiosks empower users to complete transactions or obtain services independently, improving efficiency and convenience in high-traffic locations. == Audience measurement and context-aware content adaptation == === Audience measurement === Cameras can be integrated into digital signage systems to enable audience measurement. They are used to detect and count viewers, estimate demographics such as age and gender, measure dwell time and attention, and sometimes analyze emotional reactions using computer vision techniques. This process is valuable for understanding audience behavior and refining business strategies. Privacy concerns are addressed by anonymizing collected data and avoiding the storage of personally identifiable information. === Context-aware digital signage === Context-aware digital signage refers to systems that adjust content based on environmental or audience data. The infrastructure supporting context awareness, including sensors and analytics systems, also facilitates the collection of audience insights. While these insights may be primarily used for reporting, optimization, or planning future campaigns rather than immediate content adjustments, they play a crucial role in the overall context-aware ecosystem. ==== Contextual information ==== Contextual information in the realm of context-aware digital signage refers to data about the environment, audience, and other factors that influence how digital signage content is displayed. This information helps the system to deliver more relevant, timely, and personalized content to its audience. Contextual information can include, but is not limited to: Audience demographics — this can involve detecting the age, gender, or even emotional state of viewers through cameras or sensors. It helps tailor content to specific audience segments, improving engagement. Time and weather — the system may adjust content based on the time of day or current weather conditions. For example, weather-appropriate content (like a raincoat ad on a rainy day) or time-specific content (like dinner menu promotions in the evening) can be shown. Emergency information — in situations of emergency, systems can prioritize displaying urgent notifications such as fire alerts, disaster warnings, or evacuation instructions. This can be crucial for public safety in crowded environments or densely populated areas. The system may adapt content in real-time to inform and guide individuals to safety, offering location-specific instructions or emergency service contacts. == Challenges == === Display blindness === Digital signage in public spaces has been found to lose visibility, significantly diminishing its ability to capture attention. This issue, known as "Display Blindness", was identified by Müller et al. and refers to the phenomenon where digital advertisements are largely overlooked by passersby. Observations indicate that many of these advertisements fail to resonate with their audience, often being irrelevant or unengaging, which leads to passive reception and reduced interaction. == Comparison with print signage == Digital signage and traditional print signage serve similar purposes by delivering visual information to a target audience, but they differ significantly in terms of flexibility, cost, maintenance, and environmental impact. Digital signage is advantageous in low-light or nighttime environments, where its internal illumination ensures visibility without the need for external lighting, unlike printed signs, which may require additional fixtures to be seen after dark. === Content and flexibility === Digital signage allows for dynamic and real-time content updates, often controlled remotely through content management systems. This makes it well-suited for environments where information chan
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The Charter on the Preservation of Digital Heritage of UNESCO defines digital heritage as embracing "cultural, educational, scientific and administrative resources, as well as technical, legal, medical and other kinds of information created digitally, or converted into digital form from existing analogue resources". Digital heritage also includes the use of digital media in the service of understanding and preserving cultural or natural heritage. The digitization of both cultural heritage and Natural heritage serves to enable the permanent access of current and future generations to culturally important objects ranging from literature and paintings to flora, fauna, or habitats. It is also used in the preservation and access of objects with enduring or significant historical, scientific, or cultural value including buildings, archeological sites, and natural phenomena. The main idea is the transformation of a material object into a virtual copy. It should not be confused with digital humanities, which uses digitizing technology to specifically help with research. There have been several debates concerning the efficiency of the process of digitizing heritage. Some of the drawbacks refer to the deterioration and technological obsolescence due to the lack of funding for archival materials and underdeveloped policies that would regulate such a process. Another main social debate has taken place around the restricted accessibility due to the digital divide that exists around the world. Nevertheless, new technologies enable easy, instant and cross boarder access to the digitized work. Many of these technologies include spatial and surveying technology to gain aerial or 3D images. Digital heritage is also used to monitor cultural heritage sites over years to help with preservation, maintenance, and sustainable tourism. It aims to observe any changes, diseases, or deterioration that may occur on objects. == Cultural and natural heritage == Digital Heritage that is not born-digital can be divided into two separate groups—digital cultural heritage and digital natural heritage. Digital cultural heritage is the maintenance or preservation of cultural objects through digitization. These are objects, in some cases entire cities, that are considered of cultural importance. These objects are sometimes able to be digitized or physically represented in minute detail. Digital cultural heritage also includes intangible heritage. These are things such as "oral traditions, customs, value systems, skills, traditional dances, diets, performances" and other unique features of a culture. Intangible heritage is particularly vulnerable to destruction due to urbanization. There are several projects and programs which concentrate on digital cultural heritage. One such project is Mapping Gothic France, which aims to document and preserve cathedrals across France using images, VR tours, laser scans, and panoramas. This allows for scientific and historical study and preservation of the cathedrals and also provides detailed access to the sites for anyone in the world. The aim of projects like these is to help with the preservation and restoration of cultural objects. After the fire at Notre-Dame de Paris in 2019, digital scans are a major component in the ongoing restoration. Digital natural heritage pertains to objects of natural heritage that are considered of cultural, scientific, or aesthetic importance. Digital heritage in this instance is used not only to grant access to these objects, but to monitor any changes over time, such as with plant or animal habitats. Geographic information systems are a form of technology that is used primarily in the study of natural heritage. Western Australia has one such digital heritage project where they have created a digital repository of native plants important to both the region and the Aboriginal people. This is in order to protect and preserve the important biological heritage of Western Australia. == Educational impact == The digitization of these heritage objects has impacts around the world and across many disciplines. The increase of digital items means that people, especially the youth, are able to learn about new objects and cultures online through various media. They provide viewers with a more in-depth experience with an item or place, instead of just an image. The media is also able to be curated to age- or educational-level appropriateness, making learning easier. Some of the technology used in education, especially in museums, includes mobile apps, virtual reality, social media, and video games. Cultural heritage institutions are using this technology to try to expand access, increase appreciation for these items, and to gain new viewpoints on their collections. Digital heritage also helps scientists, archeologists, or other historians and specialists collect data on these objects, providing more information on the objects and the past. Digital Heritage is still currently being studied and improved by several sectors invested in cultural and intellectual preservation. It is particularly of interest to museums, governments, and academic institutions. Research by these groups are creating new concepts, methodologies, and techniques for the implementation of digital heritage to protect this type of cultural and natural heritage. As new technologies are created, museums and other heritage institutions are provided with more ways of disseminating their information and engaging with the public. A lack of resources within certain groups may still hinder everyone from accessing digital heritage. == Technologies used == The digitization of cultural heritage is attained through several means. Some of the main technology used is spatial and surveying technology. Space archaeological technology - Observations from space satellites are non-intrusive and can be integrated with other technologies on the ground. It is used to photograph vast areas of earth and help with research. Remnants of ancient civilizations or other human objects are also able to be spotted via satellite imaging. Unmanned aerial vehicles - UAV, such as drones, are commonly used in digitization of cultural heritage objects. The Great Wall of China is one such site that has been digitized and analyzed through unmanned aerial vehicle investigation. The resulting images, 3-D scans, maps, and other data are used to evaluate and maintain the Great Wall. Laser Scanning - Laser scanning is used to scan an area and recreate spatially accurate depictions, such as a 3D model. Virtual and Augmented Reality - VR is used primarily for education but does have uses for reconstruction and research. It is used to provide users with an immersive experience, as though they are actually at the site. Geographic Information systems - GIS are used primarily to study objects and sites over time. It is also important in studying the socioeconomic status of the past. 3D Modeling - 3D modeling has become more widely used due to an increase in technology that works specifically with heritage sites. It is often used in tandem with GIS to reconstruct objects for restoration, documentation, preservation, and educational purposes. Data is collected using satellite or other aerial imaging and ground-based imaging. There is some concern about the accuracy and authenticity of these types of digital reconstructions and their effects on the sites themselves. A major barrier to digital heritage is the amount of resources it takes to undertake such projects, such as money, time, and technology. Money and the lack of qualified personnel are two that are considered the most obstructive. This is especially an issue in less developed areas or within underfunded groups such as minorities. == Virtual heritage == A particular branch of digital heritage, known as "virtual heritage", is formed by the use of information technology with the aim of recreating the experience of existing cultural heritage, as in (approximations of) virtual reality. It is hard to differentiate this branch from the core contribution of digital heritage which is storing the heritage data digitally. Parsinejad et al. developed two techniques for Digital Twinning of the architectural assets and representation of the physical assets virtually in the museum context. Two techniques are hand recording and digital recording and both have challenges in adoption and implementation of Digital Twin as a revolutionary concept. == Digital heritage stewardship == Digital heritage stewardship is a form of digital curation which is modeled after collaborative curation. Digital heritage stewardship means stepping away from typical curatorial practices (e.g. discovering, arranging, and sharing information, material, and/or content) in favor of practices which allow its stakeholders the opportunity to contribute historical, political, and social context and culture. The collaborative practice encourages the creation, engagement, and maintena
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NexDock is a series of lapdock devices (containing a laptop screen, keyboard, trackpad, and battery connected to a phone or other device) sold by Nex Computer LLC. The product can be used with mobile desktop environments, including Samsung DeX and the former Windows Continuum. Critical reception for the series has been mixed, with reviewers praising the concept's utility for mobile productivity while noting hardware limitations and its niche appeal. == History == The first NexDock was introduced in 2016 through a successful Indiegogo campaign. Its development coincided with interest in smartphone-powered desktop interfaces, and it was marketed as a companion for Windows 10 Mobile's Continuum feature. Subsequent models, often launched via Kickstarter, added features like higher-resolution displays, touchscreens, and convertible hinges to adapt to the growing capabilities of smartphones. == Models == === NexDock (Original, 2016) === The first model featured a 14.1-inch 1366x768 display and connected primarily via a mini HDMI port. === NexDock 2 (2019) === This model introduced a 13.3-inch 1080p IPS display and a USB-C port, improvements aimed at better supporting platforms like Samsung DeX. === NexDock Touch (2020) === A touchscreen was added to the 13.3-inch display, allowing for more direct interaction with the connected device's operating system. === NexDock 360 (2021) === This version incorporated a 360-degree hinge, allowing the device to be used in laptop, tablet, tent, or stand modes. === NexDock Wireless (2023) === Wireless display connectivity was the key feature of this model, offering a cable-free connection to compatible phones and computers. === NexDock XL (2023) === The screen size was increased to 15.6 inches. It retained the 360-degree hinge and also offered a version with wireless charging for a connected phone. == Reception == Reviews of NexDock products have been mixed, generally praising the concept while pointing out execution flaws. The devices are often lauded for their utility with Samsung DeX, turning a high-end Samsung phone into a viable portable workstation. A review of the NexDock 2 from ZDNet concluded it was a "great companion for the modern road warrior," and Digital Trends called the original a "no-brainer shell" for expanding a phone's capability. However, reviewers have consistently highlighted hardware limitations. In its review of the NexDock Touch, TechRadar stated that while it was a "compelling package for a very specific niche," the "trackpad and keyboard are a bit of a letdown and the screen could be brighter." This sentiment was echoed in other reviews, with criticism often aimed at the trackpad's performance and feel. A review of the NexDock 2 from Android Authority described the experience as being "janky at times," concluding that the device "delivers on its promise — sort of." A common point across many reviews is that the overall performance is entirely dependent on the power of the connected phone, and the experience is often best suited for light productivity tasks rather than replacing a dedicated laptop.
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An imaging phantom, or simply phantom (less commonly spelled fantom), is a specially designed object that is scanned or imaged in the field of medical imaging to evaluate, analyze, and tune the performance of various imaging devices. A phantom is more readily available and provides more consistent results than the use of a living subject or cadaver, while also avoiding direct risks to living subjects. Phantoms were originally employed in 2D x-ray–based imaging techniques such as radiography or fluoroscopy, but more recently phantoms with desired imaging characteristics have been developed for 3D techniques such as SPECT, MRI, CT, ultrasound, PET, and other imaging modalities. == Design == A phantom used to evaluate an imaging device should respond in a similar manner to how human tissues and organs would act in that specific imaging modality. For instance, phantoms made for 2D radiography may hold various quantities of x-ray contrast agents with similar x-ray absorbing properties (such as the attenuation coefficient) to normal tissue to tune the contrast of the imaging device or modulate the patient's exposure to radiation. In such a case, the radiography phantom would not necessarily need to have similar textures and mechanical properties since these are not relevant in x-ray imaging modalities. However, in the case of ultrasonography, a phantom with similar rheological and ultrasound scattering properties to real tissue would be essential, but x-ray absorbing properties would not be relevant. The term "phantom" describes an object that is designed to resemble human tissue and can be evaluated, analyzed or manipulated to study the performance of a medical device. Phantoms are created using a digital file that is rendered through magnetic resonance imaging (MRI) or computer-aided design (CAD). The digital files allow for quick modifications that are read by the 3D printer. The 3D printer will create the product in successive layers using polymeric materials. There are several types of phantoms including tissue-mimicking, radiological phantoms, dental phantoms, BOMABs (used to calibrate whole-body counters), and more.
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Comet is a web application model in which a long-held HTTPS request allows a web server to push data to a browser, without the browser explicitly requesting it. Comet is an umbrella term, encompassing multiple techniques for achieving this interaction. All these methods rely on features included by default in browsers, such as JavaScript, rather than on non-default plugins. The Comet approach differs from the original model of the web, in which a browser requests a complete web page at a time. The use of Comet techniques in web development predates the use of the word Comet as a neologism for the collective techniques. Comet is known by several other names, including Ajax Push, Reverse Ajax, Two-way-web, HTTP Streaming, and HTTP server push among others. The term Comet is not an acronym, but was coined by Alex Russell in his 2006 blog post. In recent years, the standardisation and widespread support of WebSocket and Server-sent events has rendered the Comet model obsolete. == History == === Early Java applets === The ability to embed Java applets into browsers (starting with Netscape Navigator 2.0 in March 1996) made two-way sustained communications possible, using a raw TCP socket to communicate between the browser and the server. This socket can remain open as long as the browser is at the document hosting the applet. Event notifications can be sent in any format – text or binary – and decoded by the applet. === The first browser-to-browser communication framework === The very first application using browser-to-browser communications was Tango Interactive, implemented in 1996–98 at the Northeast Parallel Architectures Center (NPAC) at Syracuse University using DARPA funding. TANGO architecture has been patented by Syracuse University. TANGO framework has been extensively used as a distance education tool. The framework has been commercialized by CollabWorx and used in a dozen or so Command&Control and Training applications in the United States Department of Defense. === First Comet applications === The first set of Comet implementations dates back to 2000, with the Pushlets, Lightstreamer, and KnowNow projects. Pushlets, a framework created by Just van den Broecke, was one of the first open source implementations. Pushlets were based on server-side Java servlets, and a client-side JavaScript library. Bang Networks – a Silicon Valley start-up backed by Netscape co-founder Marc Andreessen – had a lavishly financed attempt to create a real-time push standard for the entire web. In April 2001, Chip Morningstar began developing a Java-based (J2SE) web server which used two HTTP sockets to keep open two communications channels between the custom HTTP server he designed and a client designed by Douglas Crockford; a functioning demo system existed as of June 2001. The server and client used a messaging format that the founders of State Software, Inc. assented to coin as JSON following Crockford's suggestion. The entire system, the client libraries, the messaging format known as JSON and the server, became the State Application Framework, parts of which were sold and used by Sun Microsystems, Amazon.com, EDS and Volkswagen. In March 2006, software engineer Alex Russell coined the term Comet in a post on his personal blog. The new term was a play on Ajax (Ajax and Comet both being common household cleaners in the USA). In 2006, some applications exposed those techniques to a wider audience: Meebo’s multi-protocol web-based chat application enabled users to connect to AOL, Yahoo, and Microsoft chat platforms through the browser; Google added web-based chat to Gmail; JotSpot, a startup since acquired by Google, built Comet-based real-time collaborative document editing. New Comet variants were created, such as the Java-based ICEfaces JSF framework (although they prefer the term "Ajax Push"). Others that had previously used Java-applet based transports switched instead to pure-JavaScript implementations. == Implementations == Comet applications attempt to eliminate the limitations of the page-by-page web model and traditional polling by offering two-way sustained interaction, using a persistent or long-lasting HTTP connection between the server and the client. Since browsers and proxies are not designed with server events in mind, several techniques to achieve this have been developed, each with different benefits and drawbacks. The biggest hurdle is the HTTP 1.1 specification, which states "this specification... encourages clients to be conservative when opening multiple connections". Therefore, holding one connection open for real-time events has a negative impact on browser usability: the browser may be blocked from sending a new request while waiting for the results of a previous request, e.g., a series of images. This can be worked around by creating a distinct hostname for real-time information, which is an alias for the same physical server. This strategy is an application of domain sharding. Specific methods of implementing Comet fall into two major categories: streaming and long polling. === Streaming === An application using streaming Comet opens a single persistent connection from the client browser to the server for all Comet events. These events are incrementally handled and interpreted on the client side every time the server sends a new event, with neither side closing the connection. Specific techniques for accomplishing streaming Comet include the following: ==== Hidden iframe ==== A basic technique for dynamic web application is to use a hidden iframe HTML element (an inline frame, which allows a website to embed one HTML document inside another). This invisible iframe is sent as a chunked block, which implicitly declares it as infinitely long (sometimes called "forever frame"). As events occur, the iframe is gradually filled with script tags, containing JavaScript to be executed in the browser. Because browsers render HTML pages incrementally, each script tag is executed as it is received. Some browsers require a specific minimum document size before parsing and execution is started, which can be obtained by initially sending 1–2 kB of padding spaces. One benefit of the iframes method is that it works in every common browser. Two downsides of this technique are the lack of a reliable error handling method, and the impossibility of tracking the state of the request calling process. ==== XMLHttpRequest ==== The XMLHttpRequest (XHR) object, a tool used by Ajax applications for browser–server communication, can also be pressed into service for server–browser Comet messaging by generating a custom data format for an XHR response, and parsing out each event using browser-side JavaScript; relying only on the browser firing the onreadystatechange callback each time it receives new data. === Ajax with long polling === None of the above streaming transports work across all modern browsers without negative side-effects. This forces Comet developers to implement several complex streaming transports, switching between them depending on the browser. Consequently, many Comet applications use long polling, which is easier to implement on the browser side, and works, at minimum, in every browser that supports XHR. As the name suggests, long polling requires the client to poll the server for an event (or set of events). The browser makes an Ajax-style request to the server, which is kept open until the server has new data to send to the browser, which is sent to the browser in a complete response. The browser initiates a new long polling request in order to obtain subsequent events. IETF RFC 6202 "Known Issues and Best Practices for the Use of Long Polling and Streaming in Bidirectional HTTP" compares long polling and HTTP streaming. Specific technologies for accomplishing long-polling include the following: ==== XMLHttpRequest long polling ==== For the most part, XMLHttpRequest long polling works like any standard use of XHR. The browser makes an asynchronous request of the server, which may wait for data to be available before responding. The response can contain encoded data (typically XML or JSON) or Javascript to be executed by the client. At the end of the processing of the response, the browser creates and sends another XHR, to await the next event. Thus the browser always keeps a request outstanding with the server, to be answered as each event occurs. ==== Script tag long polling ==== While any Comet transport can be made to work across subdomains, none of the above transports can be used across different second-level domains (SLDs), due to browser security policies designed to prevent cross-site scripting attacks. That is, if the main web page is served from one SLD, and the Comet server is located at another SLD (which does not have cross-origin resource sharing enabled), Comet events cannot be used to modify the HTML and DOM of the main page, using those transports. This problem can be sidestepped by creating a proxy server in
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Bridgefy is a Mexican software company with offices in Mexico and California, the United States, dedicated to developing mesh-networking technology for mobile apps. It was founded circa 2014 by Jorge Rios, Roberto Betancourt and Diego Garcia who conceived the idea while participating in a tech competition called StartupBus. Bridgefy's smartphone ad hoc network technology, apparently using Bluetooth Mesh, is licensed to other apps. The app gained popularity during protests in different countries since it can operate without Internet, using Bluetooth instead. Aware of the security issues of not using cryptography and the criticism surrounding it, Bridgefy announced in late October 2020 that they adopted the Signal protocol, in both their app and SDK, to keep information private, though security researchers have demonstrated that Bridgefy's usage of the Signal Protocol is insecure. == Usage == The app gained popularity as a communication tactic during the 2019–2020 Hong Kong protests and Citizenship Amendment Act protests in India, because it requires people who want to intercept the message to be physically close because of Bluetooth's limited range, and the ability to daisy-chain devices to send messages further than Bluetooth's range. == Security == In August 2020, researchers published a paper describing numerous attacks against the application, which allow de-anonymizing users, building social graphs of users’ interactions (both in real time and after the fact), decrypting and reading direct messages, impersonating users to anyone else on the network, completely shutting down the network, performing active man-in-the-middle attacks to read messages and even modify them. In response to the disclosures, developers acknowledged that "no part of the Bridgefy app is encrypted now" and gave a vague promise to release a new version "encrypted with top security protocols". Later developers said they plan to switch to Signal Protocol, which is widely recognized by cryptographers and used by Signal and WhatsApp. The Signal Protocol was integrated into the Bridgefy app and SDK by late October 2020, with the developers claiming to have included improvements such as the impossibility of a third person impersonating any other user, man-in-the-middle attacks done by modifying stored keys, and historical proximity tracking, among others. However, in 2022, the same security researchers, now including Kenny Paterson, published a paper describing how Bridgefy's usage of the Signal Protocol was incorrect, failing to remedy the previously discovered issues. The researchers performed a demonstration, showing that it was possible for users to intercept messages intended for others without the sender noticing. The researchers disclosed the vulnerabilities to the developers of Bridgefy in August 2021, but, according to the researchers, the developers had yet to resolve the issues as of June 2022. On July 31, 2023, the security firm 7asecurity released a blog post and pentest report of a white box penetration test and overall security review of the Bridgefy app in collaboration with the platform's developers. Their review, which began in November 2022 and concluded in May 2023, identified multiple critical vulnerabilities throughout the application. Many of the issues were fixed, or partially fixed, before the end of the audit, including user impersonation and biometric bypass. Bridgefy also published a blog post on August 8, 2023, announcing the audit results.
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