LOS ANGELES (AP) — Microsoft is expected to make a "major" announcement Monday. Speculation about the Los Angeles media event is that the company plans to unveil either a tablet computer or a system that uses an upcoming version of Windows to help people access TV shows and movies across a range of devices.

A Microsoft-branded tablet wouldn't come as a complete surprise. In April, Microsoft announced a $300 million, 17.6 percent stake in Barnes & Noble's Nook e-book business.

Microsoft Corp.'s next operating system, Windows 8, is designed to run desktop, laptop and tablet computers. PC makers are hoping it offers them a better chance to compete with Apple Inc.'s iPad. Windows 8 is expected to be released in September or October, in time for devices that ship for the holiday season.

"This will be a major Microsoft announcement — you will not want to miss it," the company said in an email invite to the media on Thursday. A company spokesman declined to comment further.

The event, set to start at 3:30 p.m. Pacific time, is being kept under such tight wraps that the company has declined to provide its location until Monday.