A Rewrite engine is a piece of computer software used to modify URLs for a variety of purposes.

Apache HTTP server has a rewrite engine called mod_rewrite.

mod_rewrite has been described as "the Swiss Army Knife of URL manipulation".

There are also rewrite engines for other web servers such as Microsoft's Internet Information Server (IIS).

A detailed description of Apache's mod_rewrite is available on the Apache.org website.

The primary benefits derved from using a rewrite engine are:

  • rendering complex web site structures 'search engine friendly'

  • preventing undesired 'hot linking'

Other Rewrite Engines:

For Microsoft's IIS:

IISRewrite from Qwerksoft

ISAPI_Rewrite from isapirewrite.com