Spinx is a powerful search server that helps you to extend functions of your website
Sphinx - open source full text search server. A distinctive feature is the high speed indexing and search quality. Graceful integration with existing databases, such as MySQL and PostgreSQL, as well as API for common web programming languages, make this search engine a top performer.
In other words:
Sphinx - a system that greatly improves the quality of content searches on the site. Through the use of special algorithms for text filtering, the speed and relevancy of search results increases.
What is it used for?
When a website contains of a vast number of site-based records, such as, many products in the store, or a large library of articles/documents posted on the website, the use of Sphinx allows the visitor to easily search for and receive relevant information.