Cortana - to some people its the name of the new personal assistant set to debut with Windows Phone 8.1 from Microsoft. But for a generation of gamers, its the name of the one of the most advanced AI's in the universe.
Cortana is the digital companion of Master Chief in Bungie's Halo video game series - a constant source of HUD help and an increasingly important character in the franchise. For the mobile version, Microsoft has gone so far as to have the same voice actor lend her pipes to the role.
That's Jen Taylor, a verteran voice actor who first appeared in the Halo series at its inception in 2001. Here she is talking about the character.
Other voices, including synthesised ones, will also appear on Windows Phone but the main personality belongs to Cortana. And as in the games, she'll learn more about you as you spend time together, gradually becoming the kind of personal assistant who might actually be able to help you to save the universe.
Or send texts, search the web and make appointments for your calendar.
Cortana onWindows Phone will roll out with the 8.1 update which is due over the next couple of months.