Definition of Index.php

index.html is the traditional filename for such a page, but most modern HTTP servers offer a configurable list of filenames that the server can use as an index. If a server is configured to support server-side scripting, the list will usually include entries allowing dynamic content to be used as the index page (e.g. index.php, index.shtml, default.asp). An example is the popular open source web server Apache, where the list of filenames is controlled by the DirectoryIndex directive in the main server configuration file or in the configuration file for that directory.