From Seo Wiki - Search Engine Optimization and Programming Languages
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 for the following purposes:
- 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 browsers typically have some form of web annotation system built-in as standard. Alternate systems include:
- A.nnotate - notes on web pages and uploaded PDF/Word documents attached to highlighted text
- Delicious - allows users to share and organize bookmarks using tags. Provides a number of search feeds to facilitate mashups.
- Diigo - for highlighting text and posting sticky notes on webpages.
- Reframe It - a browser extension that allows users to comment publicly or privately in a margin on the live website, adjacent to the text or photo the comment references.
- 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.
- Sidewiki - a Google service that is available via toolbars for Firefox and IE
- 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 - highlight or sticky note content, organize annotations and share with colleagues by using either a toolbar or bookmarklet (IE or Firefox).
Former systems include:
- Annotea - a W3C project that tried to establish a standard for web annotation.
- Nethernet - a multi-player online game, now closed.
- ThirdVoice - a notable system launched in 1999 that shut down due to lack of success in April 2001.
- Wikalong - implemented a wiki which anyone could use to describe or comment or discuss a web page as it appeared on a certain date.
- Stet - formerly used for the GPLv3 drafts.
- Signer, Beat: "An Architecture for Open Cross-Media Annotation Services", Proceedings of WISE 2009, 10th International Conference on Web Information Systems Engineering, Poznan, Poland, October 2009
- "Five Ways to Mark Up the Web", Techcrunch April 10, 2007
- "Top Web Annotation Tools: Annotate+Bookmark+Collaborate", MakeUseOf May 13, 2007