San Fransisco: Hewlett-Packard Co, the world's largest maker of personal computers, is "studying" Google Inc's Android operating system software for use on scaled-down notebook PCs known as netbooks.

"We are interested in understanding all the various operating-system choices in the marketplace that could be used by our competitors," said Marlene Somsak, spokeswoman for Palo Alto, California-based Hewlett-Packard. "With respect to Google Android, we're studying the OS in general and looking at its computing and communications capabilities."

A shift of Android use to PCs from smart phones would encroach on a market dominated by Microsoft Corp, whose Windows operating-system software is used on more than 90 per cent of the world's PCs. Unlike Windows, Android is open-source software that is distributed for free and can be modified by developers.

Google said it had no announcements to make as yet on computer makers adopting its software.

"The Android smart-phone platform was designed from the beginning to scale downward to feature phones and upward to mobile Internet devices and netbook-style devices," said Google spokeswoman Katie Watson. "We look forward to seeing what contributions are made and how an open platform spurs innovation."

Google started Android, based on the Linux open-source operating system, in 2007 as part of an industry effort to create a free software system for phones. T-Mobile USA Inc, the fourth-biggest wireless carrier in the US, offers an Android phone called the G1.

Hewlett-Packard declined to comment on whether any products using Android are in development. The company last year began selling a netbook line called the Mini, and sells models powered by Windows Vista and Linux. Netbooks, designed for users who want a low-cost PC for surfing the Internet.