A Web address that is easy for a user as well as a search engine to decipher. In a friendly URL, the programming code is hidden under a more readable name.
Friendly vs. Dirty
In contrast, the "dirty URL" displays some of the underlying code and is thus more prone to hacking. For example, a user might look up a term on a dictionary site that uses the ASP server technology. If the term were "BGA," the query string sent to the content provider might look like
techdefs.com/lookup.asp?d=BGA. However, the friendly URL for this query might be
techdefs.com/lookup=BGA, which offers a human readable and search engine friendly address, while hiding the server method. See
URL shortening.