What is Moodle?
Moodle is a Course Management System (CMS), also known as a Learning Management System (LMS) or a Virtual Learning Environment (VLE). It is a free web application that educators can use to create effective online learning courses.
There are now more than 54,000 Moodle sites around the world, in more than 200 countries, and over 1,000,000 (one million!) teachers and Moodle users registered on the main community site - www.moodle.org.
More infomation about Moodle can be found here.