Software giant Microsoft last night unveiled its first tablet computer, the Surface, in a major hardware launch clearly designed to take on long-term rival Apple's market-ruling iPad.
CEO Steve Ballmer described the device - complete with a built-in stand and ultra thin covers which can be used as a keyboard in a range of colours - as a tablet that "works and plays."
"The Surface is a PC, the Surface is a tablet, and the Surface is something new that we think people will absolutely love," he said.
No prices or release dates were given, but the Surface is expected to go on sale in autumn, with retail prices "competitive with a comparable ARM tablet or Intel Ultrabook-class" computers, Microsoft said.
There were spontaneous bursts of applause and whoops from tech journalists and bloggers as key features of the new tablet, which has a slightly bigger screen than the iPad, but in wide-screen movie-style 16:9 format.
There was also one nerve-jangling moment for Windows Live Division chief Steven Sinofsky, when the first Surface model he was demonstrating failed to respond to a touch command. To his relief, a replacement worked immediately.
"It feels natural in your hands," he told the invite-only event, shrouded in secrecy reminiscent of Apple icon Steve Jobs, and held in a venue underlining cutting-edge design values, traditionally not Microsoft's strong point.
A version of the Surface tablet running on Windows RT software tailored for ARM mobile device chips will measure 9.3 millimetres thick and weigh 676 grams. It boasts a 26.9 centimetre high-definition screen and will be available with 32 or 64 gigabytes of memory.
A model powered by Windows 8 Pro weighs 903 grams and will also be available with 64 or 128 gigabytes of memory.
"It's a whole new community of computing devices from Microsoft," Ballmer said. "It embodies the notion of hardware and software really pushing each other."
The Surface features a flip-out rear "kickstand" to prop it up like a picture frame and can be combined with a 3mm-thick Touch Cover that, when opened, acts as a keypad so tablets could be switched into "desktop" mode. There is also a 5mm-thick Type Cover with moving keys for a more traditional typing feel.
The keypad-cover attaches with a magnetic clasp familiar to iPad users, combining to feel like a book in weight and form, as confirmed when journalists were briefly given a brief chance to hold the device after the presentation.
Microsoft did not specify when the tablet would be available but it is likely to be timed with the release of Windows 8 software later this year.
Microsoft, which built its fortune by specialising in software and leaving the job of making computers or other devices to partners, has had mixed results from its hardware ventures.
The Washington-based technology giant has stamped its brand on personal computer keyboards, headsets, speakers, webcams and mouse controllers.
Microsoft has occasionally weighed in with more significant hardware when it appeared that rivals were running away with the market. The company's most successful effort in devices has been its Xbox gaming console, in contrast to its failed music player known as Zune.
Microsoft this month unveiled a SmartGlass application that developers can use to synch iPads or other tablet computers to Xbox 360 consoles. Zune handheld digital media players were released in late 2006 in a Microsoft challenge to Apple's culture-changing iPod devices.
Microsoft discontinued Zune hardware last year. But it continues to operate its Zune service offering online music, films and other entertainment content, weaving it into the offerings available on Internet-linked Xbox 360 videogame consoles.
