This presentation outlines the 9 themes of digital citizenship, information on your digital footprint, and social networking. The 9 themes are based on the work of Mike Ribble, author of "Digital Citizenship in Schools". His website is also linked.
If you're interested in the current size of your own digital footprint, you can download a copy of the Personal Digital Footprint Calculator.
How aware are you of your digital dossier? Watch this time line of Andy's lifespan and find out...