WordPress is an open source Content Management System (CMS), often used as a blog publishing application, powered by PHP and MySQL. It has many features including a plug-in architecture and a template system. WordPress can be deployed using various methods on a hosting environment. WordPress has a template processor system. Users can re-arrange widgets without editing PHP or HTML code; they can also install and switch between themes. The PHP and HTML code in themes can also be edited for more advanced customizations. WordPress also features integrated link management; a search engine-friendly, clean permalink structure; the ability to assign nested, multiple categories to articles; and support for tagging of posts and articles.