How browsers might use <link>

Although the HTML standard does not require browsers to do anything with the information provided by the <link> tag, it’s not hard to envision how this information might be used to enhance the presentation of a document.

As a simple example, suppose you consistently provide <link> tags for each of your documents that define next, prev, and parent links. A browser could use this information to place a standard toolbar at the top or bottom of each document containing buttons that would jump to the appropriate related document. By relegating the task of providing simple navigational links to the browser, you are free to concentrate on the more important content of your document.

As a more complex example, suppose a browser expects to find a <link> tag defining a glossary for the current document, and that this glossary document is itself a searchable document. Whenever a reader clicked on a word or phrase in the document, the browser could automatically search the glossary for the definition of the selected phrase, presenting the result in a small pop-up window.

As the Web and HTML evolve, expect to see more and more uses of the <link> tag to explicitly define document relationships on the Web.