Moodle is a web based collaborative tool similar to Blackboard that is also aimed at higher education. It offers a number of tools that help students collaborate like forums, chat rooms, and wikis. It also supports interactive online quizes, surveys, and lessons.
Moodle is a capable replacement for Blackboard, but its static web-based interface feels dated. It currently doesn't push the 'lessons' to the student, so it cannot be used as a real-time presentation tool.
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