Microsoft has shaken up its Surface family with the introduction of its first-ever laptop - the Surface Book, Digital Spy reports.

The Windows 10 machine has a 13.5-inch display with an eye-watering pixel density of 267PPI, optically bonded so it appears very close to the glass.

It's display even detaches for those who are after a tablet experience - although you can always buy the new Surface Pro 4 for that.

Running off the latest Intel processors with an Nvidia GeForce GPU and GDDR5 memory, Microsoft claims that the Surface Book is "the fastest 13-inch laptop ever made", pound for pound, allegedly up to twice as quick as Apple's latest Macbooks.

"What if we could do for laptops what we did for tablets," said a Microsoft spokesperson. "That's what we did. We made the ultimate laptop. We made Surface Book. This is the first laptop built by Microsoft, and it redefines everything."

The laptop weighs just 1.6 lbs and is 7.7mm thin. Its keyboard is backlit and provides a silent typing experience, while the glass trackpad beneath it has five points of touch sensitivity.

The Surface Book is available to pre-order from October 7, priced at $1,499. Orders will ship out on October 26.