Google is developing an operating system (OS) for personal computers, in a direct challenge to market leader Microsoft and its Windows system. Google Chrome OS will be aimed initially at small, low-cost netbooks, but will eventually be used on PCs as well. Google said netbooks with Chrome OS could be on sale by the middle of 2010. "Speed, simplicity and security are the key aspects of Google Chrome OS," the firm said in its official blog. The operating system, which will run on an open source licence, was a "natural extension" of its Chrome browser, the firm said. The news comes just months before Microsoft launches the latest version of its operating system, called Windows 7. 'Back to basics' "We're designing the OS to be fast and lightweight, to start up and get you on to the web in a few seconds," said the blog post written by Sundar Pichai, vice-president of product management, and Google's engineering director Linus Upson. Both men said that "the operating systems that browsers run on were designed in an era where there was no web" and that this OS was "our attempt to rethink what operating systems should be". To that end, the search giant said the new OS would go back to basics. "We are completely redesigning the underlying security architecture of the OS so that users don't have to deal with viruses, malware and security updates. "It should just work," said Google. Google already has an operating system for mobile phones called Android which can also be used to run on netbooks. Google Chrome OS will be aimed not just at laptops but also at desktops for those who spend a lot of time on the web. 'Truly competitive' The announcement could dramatically change the market for operating systems, especially for Microsoft, the biggest player with around 90% share. "This announcement is huge," said Rob Enderle, industry watcher and president of the Enderle Group. "This is the first time we have had a truly competitive OS on the market in years. This is potentially disruptive and is the first real attempt by anyone to go after Microsoft. "Google is coming at this fresh and, because it is based on a set of services that reside on the web, it is the first really post-web operating system, designed from the ground up, and reconceived for a web world," Mr Enderle told the BBC. Source: BBC