To tap the fast growing web and personal computers market, internet giant Google is working on an operating system, a move that is likely to pose a stiff challenge to Microsoft’s dominance.

“We are working on an operating system... we feel, when other operating systems became part of the Web, the world was not connected the way it is today,” Google Global Sales Operations and Business Development President Nikesh Arora said.

“Whether our operating system replaces the existing ones, I don’t know. Customers will choose that,” he said, while speaking at the HT Leadership Summit here.

In July, Google announced plans to launch its own operating system for personal computers. The planned open source ‘Google Chrome Operating System’ is expected to be available in the second half of 2010.

Microsoft has about 90 per cent share in the global market for operating systems.

“Google Chrome Operating System is an open source, lightweight operating system that will initially aim at netbooks... Later this year, we will open-source its code, and net-books running Google Chrome Operating System will be available for consumers in the second half of 2010,” Google had said in a blog.

The blog, which was written by Vice-President (Product Management) Sundar Pichai and Engineering Director ELinus Upson, said the operating systems that browsers run on were designed in an era where there was no web.