WordPress looks for the Plugin Header in the php files. The main Plugin file should have a header like this:
<?php
/**
* Plugin Name: Name Of The Plugin
* Plugin URI: http://URI_Of_Page_Describing_Plugin_and_Updates
* Description: A brief description of the Plugin.
* Version: The Plugin's Version Number, e.g.: 1.0
* Author: Name Of The Plugin Author
* Author URI: http://URI_Of_The_Plugin_Author
* License: A "Slug" license name e.g. GPL2
*/
For more info, look here: http://codex.wordpress.org/Writing_a_Plugin#File_Headers
Happy Coding,
Kuchenundkakao