Andy just got spammed. Tom is listening to a podcast. Molly is thinking about her thesis and reading a book. (Good for you, Molly.) How do I know all of this about people I’ve never met before? They are Twittering, which is the type of rapid fire, short bursts of communication you do on a new social networking site called Twitter.

Twitter was designed to help friends keep in touch with friends on a minute-by-minute basis. The messages you can post on Twitter are limited to 140 characters. Participants are answering the most basic of questions: “What are you doing right now?” The dispatches are meant to be a running diary of your life shared with friends.

Short entries, anything one can say in 140 characters or less, are called micro blogs. They can be sent out to anyone who signs up to receive your Twitter feed. Readers of your feed don’t need to be sitting at their computer waiting for your update either. They can access Twitter feeds on their phones through text messaging, IM, or email as well. Twitter is free but you pay your phone service provider for sent messages. Messages on Twitter are naturally called tweets.

Parents are going to freak at the thought of Twitter–an even greater waste of time, and potentially more dangerous than Facebook, MySpace, or others because kids will be divulging their whereabouts in real time. And since Twitter is always with you on your cell phone, good judgment before sending out a message may not have time to prevail. But kids, who want to stay in touch constantly and who love to document their lives, are going to be all-atwitter with Twitter. One journalist on NPR likened it to “haiku on the Internet.” Check it out at Twitter and see if you agree.