AutoLink

An autolink is a hyperlink added automatically to a hypermedia document, after it has been authored or published. Segments of the hypermedia are identified through a process of pattern matching. For example, in hypertext, the software could recognise textual patterns for street addresses, phone numbers, ISBNs, or URLs.

In a distributed hypermedia system, such as the World Wide Web, autolinking can be carried out by client or server software. For example, a web server could add links to a web page as it sends it to a web browser. A browser can also add links to a page after it has received it from the server.

AutoLink is a feature of the Google Toolbar. Users can convert street addresses, ISBNs in a web page in their browser to links by clicking a button on Google Toolbar. The links direct the users to Google Maps for street addresses and Amazon.com for book information.

Since introduced in February 2005, there has been a lot of controversy about this feature. Some webmasters expressed their concerns over the AutoLink feature claiming that Google had no rights to modify their webpages or to direct the users to a commercial website such as Amazon.

This caused Barnes & Noble, a competitor of Amazon, to link all ISBNs on their site back to themselves to prevent people clicking them to take them to their competitor.

Google sceptics compare it with Microsoft's unpopular SmartTags, which ultimately proved too controversial and were dropped.

AutoLinker is a plugin application which has been developed for vBulletin forum software. It allows keywords set by the board administrator to be turned into hyperlinks or popups automatically any time they are used in a forum post or message.

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Wikipedia