Twitter is a microblogging website allowing users to update their presence and inform family, friends and followers of their everyday activities. With a large education-based community having grown in Twitter, many teachers and administrators are finding it a useful way to network and learn about resources and education related news. Recently Lee Levever, of Common Craft created a short video that explains what Twitter is and how people are finding it useful. Twitter in Plain English might help you explain to colleagues and friends all of the benefits Twitter offers.
Speaking of Twitter, if you haven't seen Craig Nansen's Twitter/GoogleMaps mashup, it is worth a look.