As consultant Marc Prensky calculates it, the life arc of a typical 21-year-old entering the workforce today has, on average, included 5,000 hours of video game playing, exchange of 250,000 e-mails, instant messages, and phone text messages, 10,000 hours of mobile phone use. To that you can add 3,500 hours of time online.

Our work at the Pew Internet Project shows that an American teen is more likely than its parents to own a digital music player such as an iPod, to have posted writing, pictures or video on the internet, to have created a blog or profile on a social networking website such as MySpace, to have downloaded digital content – songs, games, movies or software, and to have snapped a photo or video with a phone.