Microsoft has revealed that Windows 10 will bring its voice-controlled assistant Cortana to PCs. It also unveiled a headset that it said would one day project the operating system over views of the real world. In addition, the firm announced that the OS upgrade would be offered free of charge for devices running Windows 8, Windows 7 and Windows Phone. MORE@BBC
Windows 10 to get “holographic headset” and Cortana in free upgrade
By Leo Kelion, BBC