Web annotation
A Web annotation is an online annotation associated with a web resource, typically a web page. With a Web annotation system, a user can add, modify or remove information from a Web resource without modifying the resource itself. The annotations can be thought of as a layer on top of the existing resource, and this annotation layer is usually visible to other users who share the same annotation system, making it a type of social software tool.
Web annotation can be used:
- to rate a Web resource, such as by its usefulness, user-friendliness, suitability for viewing by minors.
- to improve or adapt its contents by adding/removing material, something like a wiki.
- as a collaborative tool, e.g. to discuss the contents of a certain resource.
- as a medium of artistic or social criticism, by allowing Web users to reinterpret, enrich or protest against institution or ideas that appear on the Web.
- to quantify transient relationships between information fragments.
Web annotation systems
Web annotation systems are typically implemented as part of standard web browsers. Those currently in release and under development include:
- A.nnotate[1] - notes on web pages and uploaded PDF/Word documents attached to highlighted text
- co-ment[2] - a free software Web service for uploading or creating on-line texts, submitting them to comments from designated users or the general public, and processing the comments.
- Cozimo[3] - In-browser application sharing for annotating videos and images (free API).
- Diigo - for highlighting text and posting sticky notes on webpages.
- Fleck[4] - add stick-it notes to webpages and share these with other people.
- JumpKnowledge[5] - a free, web-based, cross-browser, registration-optional web page annotation tool.
- Marginalia - open-source, Javascript-based, adds text highlighting and margin note capabilities to web applications.
- PMOG - The Passively Multiplayer Online Game, uses a form of web annotation to link together websites and players in a web metagame.
- Protonotes[6] - a piece of JavaScript for websites that allows visitors to add sticky notes.
- SharedCopy - AJAX-based web annotation with cache and shorten url with easy sharing functions.
- Shiftspace - has the tag line "an open source layer above any webpage" and is based on the Greasemonkey platform for Firefox.
- Stickis - Firefox and IE toolbars that allow rich media notes to be attached to any web page. See only those from your friends anywhere you browse.
- WebNotes[7] - highlight or sticky note content, organize annotations and share with colleagues by using either a toolbar or bookmarklet (IE or Firefox).
- Wikalong - for Firefox.
Former systems:
- Annotea - a W3C project that tried to establish a standard for web annotation.
- ThirdVoice - a notable system launched in 1999 that shut down due to lack of success in April 2001.[8]