Twitter, the fast-growing microblogging and social media site, is about to change gears.

The service where users post short updates about what they are doing has received an explosion in visitors, both in the UK and the US. Twitter has become the communication tool of choice among early adopters and the tech community, a worldwide first alert news medium and a nascent marketing and customer services tool as it has thrust itself into the mainstream.

Twitter is just about to make the biggest shift in its short history by integrating its search functions into the home pages of users.

Until now if users wanted to search the outpouring of updates or "tweets", say for updates about a stock price or football team or a hotel, they had to go to a separate website – search.twitter.com – or use one of the many independent search applications that have sprung up on the web.

That hurdle is thought to have blocked many of the general public from understanding how to get beyond the criticism of Twitter as a platform for narcissists and to take advantage of Twitter's growing scale.

Biz Stone, one of Twitter's co-founders, told The Times: "Search integration is a way of introducing relevancy to people. This is not just about 'What are you doing?' but about what everyone else is doing. Twitter is about finding out what is going on out there right now in real time. This is a powerful new way of repositioning the product."

Within the next 10 days, Twitter will start putting search into the Twitter home pages of about 1 per cent of users, to test the waters and ask for feedback, before rolling it out across the network, Mr Stone said.

In Twitter users answer the question "What are you doing?" in 140 characters or less and post their updates into a personal stream.

Other users can choose to receive or "follow" those updates, or send messages directly at other users, creating networks of twitterers.

Twitter has become an essential way for millions of people to share their experiences during global events such as the election of President Obama or the plane crash in the Hudson River.

According to various analyses – Twitter does not provide official figures – more than 2.25 million tweets are posted every day, adding to a total of more than 1.1 billion tweets since the service was launched early in 2007. The site is thought to have more than 1.2 million active users and the rate of growth is accelerating. Twitter says that its active user base – several million more have Twitter accounts – increased six-fold in the last 10 months. Mr Stone told The Times that he expected the growth rate to be 10x over the next year, thanks in part to the integration of search.

Search is also likely to be central to finding a way to make money for the site. Until now the service – with no business model – has been propped up by $22 million (£16 million) of venture capital. The founders have promised to introduce a revenue stream in the next couple of months and Mr Stone said that search – finding relevant, useful information for companies – would be key.