San Francisco  - Google released its first ever internet browser on Tuesday in a long-awaited move that increased pressure on Microsoft and laid a new foundation for a mass transition to web- based computing.

A test version of the new software, named Google Chrome, was made available for download Tuesday in more than 100 countries. The open- source browser had been in secret development for over two years at the search engine giant.

According to Google, Chrome is less demanding than current browsers on the memory and chips which run computers. The main new features include a new Javascript engine called V8 that executes functions through the browser much faster and more securely than anything currently on the market.

Chrome also isolates each separate tab that is opened in the browser, making sure that the browser never crashes.

Chrome's deployment marked a new threat to Internet Explorer, the Microsoft browser which has seen its market share drop almost 20 per cent to just 73 per cent in the four years since its open source rival Firefox came out.

But Google, the world's leading internet company, has far loftier ambitions for Chrome than merely taking another chunk out of Internet Explorer. Google's goal is for Chrome to accelerate the move to browser-based applications on devices from PC's to cellphones.

By having a browser built from the ground-up to carry out complex functions, Google can make obsolete complex PC-based programs like Microsoft's cash cow, the Office productivity suite. And once PCs run everything through a browser and don't have to host gigantic programs, it also doesn't matter if they are running windows, Linux, Apple or any other operating system.

"Google (is) designing not so much a traditional Web browser, but a Web application platform," said Stephen J Waughun, author of Computerworld's Cyber Cybic blog. "Killing Internet Explorer isn't really Chrome's goal. No, killing Microsoft Office is Chrome's goal."

That should set off alarm bells in the executive office of a certain software company based near Seattle. "Memo to Steve Ballmer: If you've got a panic button, now might be a good time to hit it," wrote Tom Bemis, an editor at MarketWatch.

Other analysts also applauded the move with the main criticism being: "What took Google so long?"

"The browser is a key piece of Google's strategy, delivering "improved access to data and user behaviour without relying on Microsoft," said UBS analyst Benjamin Schachter. He cautioned however, that users might not download the browser in sufficient quantities to make a difference.

Chrome was released just days after the release by Microsoft of a new version of Internet Explorer, which Microsoft said would remain the top choice of users.

"The browser landscape is highly competitive, but people will choose Internet Explorer 8 for the way it puts the services they want right at their fingertips, respects their personal choices about how they want to browse and, more than any other browsing technology, puts them in control of their personal data online," said Dean Hachamovitch, general manager of Internet Explorer, in a statement.

Chrome was also sure to be closely examined by privacy advocates because the Mountain View, California-based company has been accused of collecting too much data on its customers.

The Chrome browser is being introduced with the appearance of the first mobile phones operating on Google's Android software. Internet surfing via cellular phones is seen as the industry's next big growth market, and Apple is also trying to capture the market with Safari on its iPhones. (dpa)