Microsoft’s annual Build conference is under way and so far one of the biggest announcements was that of its Siri-like digital assistant for Windows Phone 8.1 devices, simply called Cortana. Cortana’s name will be instantly recognisable to anyone who has played one of the Halo video games as the holographic artificial intelligence partner that accompanies Master Chief through the games.

Two years of cooperation between the Windows Phone and Bing teams have been spent on realising Cortana and now, with the release of Windows Phone 8.1, Microsoft’s mobile OS will finally have a big feather in its cap on the way to feature parity with its iOS and Android rivals.

The Verge has a fantastic piece on just how Cortana came to be, including a video tour of her in action which is well worth thebandwidth if you want the inside track.

SPOILER: they even recruited the voice actress who gave life to Cortana, Jen Taylor, to record some of her quirkier replies.