What is Asterisk? Asterisk is a free and open source framework for building communications applications. It is "like a box of Legos for people who want to create communications applications. It includes all the building blocks needed to create a PBX, an IVR system, a conference bridge and virtually any other communications app you can imagine."
In this 2-hour course, Acr0nym will give us an introductory look at what it is, what it does, and how to get started. He may even regale you with the story of how he took down the entire call center on his second day of the job. (I'll probably be in trouble for mentioning that.)