Linking to a web page other than a site's home page.

Deep linking has only begun to spark mild controversies in recent times as the Web has become more commercialized. In fact, one of the fundamental strengths of the Web is the ability for any public document to connect to any other public document.

The legality of deep linking has been called into question in several lawsuits involving well-known corporations. Opponents of deep links -- typically large corporations -- argue that deep linking unfairly eliminates the ability of the home page to contribute to brand building and ad serving functions.

Proponents of deep linking contend that the ability to link freely is central to the philosophy behind the public Internet. On a practical note, they also argue that a deep link is better than no link at all, and may even be more profitable than a home page link, especially if the target site has a poor navigational structure.

From http://www.marketingterms.com
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