Sphinx is a full-text search engine, distributed under GPL version 2.

Generally, it's a standalone search engine, meant to provide fast, size-efficient and relevant fulltext search functions to other applications. Sphinx was specially designed to integrate well with SQL databases and scripting languages. Currently built-in data sources support fetching data either via direct connection to MySQL, or from an XML pipe.

I've set up this campaign for Sphinx to help bolster support. If you've used Sphinx in your project(s), please consider donating some money to Sphinx. Contributions go directly to the Sphinx project.

Parts of this description cited on: http://sphinxsearch.com/about.html