What is Canvas used for?
Canvas is a Learning Management System. At it's most basic level, it's a way to provide an online component to courses, either to allow a course to be entirely online, or to supplement an existing "on-ground" course.
Is there specific questions you have? I'm sure Instructure, the makers of Canvas, would be happy to talk to you about it.
More info: Instructure | Learning + Tech = Awesome
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