Leading article: The tweets that became a roar

Five years ago, a mention of the words "retweet", "Tweeps" and "hashtag" would have drawn blank expressions. But today those words would cause tens of millions of faces around the world to light up in recognition. The reason is, of course, Twitter. The jargon of the micro-blogging site – which celebrates its fifth birthday today – is now part of the language of everyday life. One billion Tweets, not one of them more than 140 characters, are estimated to be fired off into cyberspace every week.

Twitter means different things to different people. Some use it as a way to communicate with a small circle of friends. Others speak to millions. Some Tweet incessantly, others are purely Tweet consumers.

The site's inventors decided on the name Twitter because it meant "a short burst of inconsequential information". So what do people Tweet about today? A Texas-based market research firm called Pear Analytics has performed an analysis and concludes that 38 per cent of Twitter traffic is conversation, 9 per cent is recommendations, 6 per cent is self-promotion and 4 per cent is news. But 40 per cent is "pointless babble". Twitter has come a long way. But, in some respects, the Tweeps have ensured that it remains true to its founding purpose.