Ever since Cronus the Titan tried to swallow his son Zeus, parents have feared being supplanted by their children. (It didn't take.) But it's only in the last few generations, as the rate of technological progress has accelerated, that children have grown up in a world significantly different from the one their parents knew, and it's only very recently that parents have seen their surpass them while they were still in the single digits. Thanks to digital media, the world is changing so rapidly today – consider that five years ago there was no Twitter, ten years ago no Facebook and fifteen years ago no Google – that even those of us who spent our childhoods programming our parents' VCRs can feel left behind.

Today is Safer Internet Day, an annual international event sponsored by Insafe to promote a safer Internet for children. Recent research on Internet life has shown that the greatest threat to kids online comes from kids themselves, both in the form of risky behaviour and online harassment, or cyber bullying. Cyber bullying can take forms such as harassing e-mails or text messages, social exclusion and spreading private photos and videos, among others, and presents a particular challenge for parents and teachers because it often happens outside the home or classroom. Because the Internet has become an essential part of kids' social lives, cyber bullying can also have more devastating effects as youth feel they have no escape.

With all the recent attention focused on stories of teenagers charged with distributing child pornography for taking sexually suggestive pictures of themselves, jobs lost due to Facebook and MySpace entries, and libel suits over blog posts, people are justifiably concerned about the permanence of material posted to the Internet. Many a teacher or parent has had to carefully explain to children or teens that whatever they post online might be seen by people other than the intended audience, and might be out there for a very long time.