An A.I construct in the Halo universe modeled after Dr. Hasley one of the main people involved in the SPARTAN project, Cortana is the most advenced A.I. in the entire Halo universe, she even hacks into UNSC(military) data if she has too. She is usually partnered up with Master Chief SPARTAN-117, she was stationed before that on a ship named the Pillar Of Autumn, where she was the ships navigator as most A.I constructs are, she is stored on The Chief in a special layer of his suit witch allows her to help his brain reflexes reach his limbs, making him faster than his normal enhanced speed, she is inserted through the helmet, but that is only where her holodisk stays, whle she spreads to every part of the chief's nueral interface, she even helps him with his radar.
"Chief, Chief can you hear me"
by Spikan January 26, 2006
A sexy bitch from halo.
Come here cortana and let me show you my spartan.
by saka2me April 03, 2008
An Artificial Intellegence created for the Xbox game HALO. Can be inserted into helmets or projected in the form of a female humanoid. Very smart, changes colors as she thinks or feels. Resembles mystique from X-Men.
"Here Chief, Take Cortana and get off this ship." -Captain Keyes
by Michael Angelo June 23, 2004