Why is Microsoft branding its Surface tablets as PCs?

What's thin, light, compact, portable and has a high-resolution touchscreen display, plus apps and software that take center stage? A tablet...right?

Not necessarily, if you're Microsoft.

Microsoft's brand new family of Surface "PCs" may look and feel like a tablet, but Microsoft wants you to know that they are machines capable of taking on the next generation of ultrabooks too.

The Surface tablets are content consumption devices like the iPad, but Microsoft is also marketing them as full-featured computers with no compromises -- tablets that you can actually use "to get things done."

"If Microsoft can deliver a satisfying PC experience through its devices and accessories, then all those manufacturers who pegged their hopes on the super-thin, super-light 'ultrabook' model have something to worry about," says The New York Times' Sam Grobart in an article on Bits.

One of the stand-out features on the Microsoft-made Surface is the new pressure-sensitive cover. The 3 mm Touch Cover attachment converts the tablet into a laptop without adding the bulk of a traditional keyboard.

"The 3 mm Touch Cover represents a step forward in human-computer interface. Using a unique pressure-sensitive technology, Touch Cover senses keystrokes as gestures, enabling you to touch type significantly faster than with an on-screen keyboard," explains Microsoft. "Touch Cover clicks into Surface via a built-in magnetic connector, forming a natural spine like you find on a book, and works as a protective cover."

Microsoft is yet to announce a full list of specs for the Surface tablets but has revealed one will run on an ARM processor with Windows RT and sport Office '15' Apps. The second will have a third-generation Intel Core processor and feature Windows 8 Pro.

The Surface for Windows RT device is expected to launch around the same time as Windows 8 and the Surface for Windows 8 Pro will arrive three months later. Microsoft has not announced a specific dollar figure for the tablets though it did say they would be priced "competitively."