I read some custom essays about Twitter which is about to hit its five billionth tweet, tweet-counting website Gigatweet has reported. At the time of writing, the number of tweets stood at 4.9 billion and was rocketing towards the milestone.

Twitter is a free social-networking tool that allows users to "micro blog" or "tweet" in less than 140 characters.

According to the GigaTweet counter, the world is hours away from its five-billionth tweet.

The site has spawned not only a new form of messaging but a new form of openness that transcends media, politics, celebrity and much more.

Twitter has also evolved into an impressive search engine that keeps users up to date with the zeitgeist of the day.

The social-networking site is also something of a news-breaking phenomenon. Before the first online story broke about the recent death of pop star Michael Jackson, the news was tweeted 5,000 times.

The service, which boasts more than 6 million monthly unique visitors and, according to Nielsen, has a 40pc user-retention rate, is rocking the worlds of media, public relations, sales, politics and much more.

The company this year raised US$35 million in venture capital from Insight Venture Partners, T. Rowe Price, Institutional Venture Partners, Spark Capital, Benchmark Capital and Morgan Stanley. More information here.