A screencast is a video recording of the actions on a user's computer screen, typically with accompanying audio, distributed through RSS. Screencasts can be thought of as video podcasts. They provide a simple means to extend rich course content to anyone who might benefit from the material but cannot attend a presentation.
The "7 Things You Should Know About..." series from the EDUCAUSE Learning Initiative (ELI) provides concise information on emerging learning practices and technologies. Each brief focuses on a single practice or technology and describes what it is, where it is going, and why it matters to teaching and learning. Use "7 Things You Should Know About..." briefs for a no-jargon, quick overview of a topic and share them with time-pressed colleagues.
In addition to the "7 Things You Should Know About…" briefs, you may find other ELI resources useful in addressing teaching, learning, and technology issues at your institution. To learn more, please visit the ELI Resources page.
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Although I have not played with this feature for very long, Camtasia allows a user to create mini-Flash quizzes that get inserted a screencast. While results do not get recorded anywhere (e.g. Blackboard, WebCT, etc.), the mini quizzes are good for review of content and can break monotonous screencasts up a bit.
I am surprised that accessibility wasn't mentioned as a downside in this article. The one drawback I've found is that faculty who use screencasting software such as Camtasia tend to not include their scripts when posting their own self-produced multimedia content.