Google says it does not yet “know enough about you” and is stepping up its efforts to collect personal information on the web.

Eric Schmidt, the Google chief executive, said yesterday that the world’s biggest internet search engine is still at a “very early” stage when it comes to gathering your personal data through the web. “This is the most important aspect of Google's expansion,” he added.

He envisaged a day when Google would be able to advise its users on everything from their career moves to how they should spend their free time, based on the collected queries they tap into Google.com.

Google already holds a vast amount of personal information about its users – ranging from the contents of e-mail (from its Gmail service) to credit card details (through Google checkout, its online payment system). The information is held in a vast network of massive “server farms” – the company's fleet of digital data centres into which it is estimated to have pumped billions of dollars.

Such information is key to success in the online advertising industry, the source of Google's massive wealth. The No1 aim is to build up precise portraits of individual consumers to better target campaigns.

As it seeks to broaden its information net, it emerged yesterday that Google is also backing a firm founded by the wife of Sergey Brin, the company’s billionaire co-founder, that aims to help people browse their genetic information online.

Google said the investment was made as the start-up 23andMe’s “goal of developing new ways to help people make sense of their genetic information will help us further our mission of organising the world’s information in this new and important field”.

Google invested about $4 million (£2 million) in the company, co-founded by Anne Wojcicki in 2006.

It is not alone among technology companies aiming to tap the human genome – perhaps the most personal information there is. Larry Ellison, the billionaire software behind Oracle, the database giant, last week told Times Online that he plans to store, track and manipulate consumers’ digital data – including their bank details, their medical records, even their genetic blueprints.

Health companies, for instance, given the opportunity to mine this information using Oracle technology, will be able to pinpoint the most effective drugs for individual patients, he suggested.

“We are getting close to this level of personalisation,” he said, citing work being done in Oracle’s labs.

On another front, applied to credit card and telephone records, a similar meeting of personal data and technology will help the authorities do a “better job in finding terrorists,” Mr Ellison said. The extension of predictive modeling techniques, already used to track markets on Wall Street, to areas such as healthcare “will help make societies more efficient,” he predicted.

Meanwhile, Autonomy, a Cambridge-based search technology specialist, has said it is exploring online “transaction hijacking”, where consumers buying items online are automatically informed, during their transaction, if a better price is offered elsewhere.

A Google spokesman stressed to Times Online that Mr Schmidt’s most recent comments referred only to the company’s web-search histories. Moreover, users have to opt in to Google's new "personalised search" tools and the company says it will not pass data on to third parties - unless ordered to do so by law.

Earlier this year, Google bowed to privacy concerns when it agreed to limit the time it keeps information about internet searches to two years.

However, the idea of Google – or any other company – taking a “big brother” role on the web will leave many civil libertarians feeling uneasy.

Data leaks have already sparked fears over personal information that can be gleaned from search behaviour. Last year, for instance, AOL, the internet portal that is part-owned by Google, accidentally released details of 20 million private search queries from 658,000 of its users to the online public.

The collection, quickly disseminated across the web by bloggers, provides a disturbingly intimate picture of some of AOL's user base. Alongside searches for Angelina Jolie and Britney Spears, darker queries typed into the AOL search engine included: "how to tell your family you're a victim of incest" and "how to kill your wife".

Potentially incriminating entries included: "cocaine in urine".

TechCrunch, a blog, said at the time: "The utter stupidity of this is staggering ... The data includes personal names, addresses, social security numbers and everything else someone might type into a search box."

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