Cortana (Halo)

Cortana is a character from the Halo games.

Cortana is a smart artificial intelligence construct. She was one of the most important figures in the Human-Covenant war, and was also John-117's partner in various combat missions as well as serving as the AI for the Halcyon-class light cruiser - UNSC Pillar of Autumn, Orbital Defense Platform - Cairo Station and Charon-class light frigate - UNSC Forward Unto Dawn.

In addition, she held vital data pertaining to the Halos, including the Activation Index from Installation 04.

Appearance
As Cortana is an AI, she has no physical body. She can communicate through comm systems and project a holographic image of herself from appropriate projectors, such as Holotanks. Her chosen avatar appears to be a naked female human, roughly in her early twenties, with purplish/bluish skin, shoulder length purplish/bluish hair cut shorter at the back, and blue symbols scrolling down her body. Cortana is said to resemble her creator, Dr. Catherine Halsey as a young woman, with a similar attitude "only unchecked by military and social protocol." Dr. Halsey says that Cortana looks somewhat like Miranda Keyes. By The Reclamation, Cortana had created a physical body for herself. She changed her face as well and her body appears as though she were wearing a circuitry-laced skin-tight suit with layered padding.

When in a different emotional state, Cortana usually changes colors. This was especially noticeable in Halo: Combat Evolved, but less so in Halo 2 and Halo 3. Only in specific instances did she produce the color-changing effect. One instance of this was right before John-117 rescued her.

Bungie took a fair of amount of artistic freedom in the evolution of her appearance throughout the Halo trilogy, noticeably from Halo: Combat Evolved to Halo 2. She had longer hair, a more-realistic humanoid figure, a much more feminine appearance, and a slightly different shade of purple. In Halo 3, she became slightly bluer and again her face, hair, and body were changed to look more feminine and realistic. In Halo: Combat Evolved Anniversary, she has her Halo 3 appearance. In Halo 4, she had darker, more opaque and realistic hair. Her facial structure had noticeably changed, her figure had become considerably more curvacious, and she gained better defined fingers and toes. The circuit-pattern mapping over her body changes between every game as well.

Personality
Cortana had a witty and playful personality and a small sense of cryptic humor laced with some sarcasm. She had neither arrogance nor false modesty about her immense capabilities, and her statements about her abilities have an objective perspective that human beings typically cannot achieve. She did get bored often and easily. In fact, it is said that seven seconds of inactivity for an AI is excruciating.

Cortana seemed to share some of her creator's memories, thoughts, opinions, and even values. When she was asked by Dr. Halsey to pick a "carrier," Cortana chose John-117 for his neural compatibility and his "luck." A similar reason used by Halsey for her choice, too. She was not only a facsimile of Dr. Halsey's mind, but also a replica of her physical form, albeit at a younger age.

Abilities
Cortana was designed to infiltrate computer systems and she is excellent at the task. She has become so intelligent that she understands Covenant technology far more than her makers and in some cases, the Covenant themselves. As of early 2553, she has never encountered a Covenant security measure that she wasn't able to bypass. In addition, she is proficient with UNSC military hardware and can run military ships and stations by herself. Indeed, the UNSC's primary use of AIs is to oversee targeting of point-defense weaponry used in space battles. For Cortana, this is merely an additional capability. She has helped out in several major battles including Operation: FIRST STRIKE. She was capable of storing large amounts of data within her holographic appearance, hiding it in the microscopic lines of code that made up her visual form. Even when she was in the Data Crystal Chip, microscopic lines of code are running through the holographic "filling."

Accessing Computers
Cortana can be transferred among various computer systems. She needed a Data Crystal Chip to move in and out of various networks, including John-117's MJOLNIR armor. However, in one instance, she merely needed to be touching another system to access it; however, this is most likely a product of John-117's upgraded armor. Quite strangely, she reverted to the data chip; this was probably because John-117's armor was badly damaged during the fall to Earth that it reverted to a back-up system, which also explains its different shield. In another instance, instead of having to be physically "plugged in" to the hologram projector, John can just hold the chip close to it. She then "walked" off it, later "touching" the chip to return to it—holographic representations of the data transfer.

Ship Managing
One of Cortana's other abilities was that she could control a variety of starships and stations and act as their AI, even though that wasn't her primary purpose. Cortana has acted as the AI of the Pillar of Autumn, Cairo Station, the Forward Unto Dawn, the Gettysburg and even the Covenant flagship Ascendant Justice. Despite it not being her purpose to act as a shipboard AI, Cortana was extremely good at it, with Captain Keyes being so pleased with her performance during the Fall of Reach, he ends up being glad he never got to initialize the Pillar of Autumn's true AI. During the time the Ascendant Justice was under human command, Cortana was able to control that ship easily once she destroyed the Covenant AI and was given full control of its systems by John-117. She proved even more adept at using the ship's technology than the Covenant were and was able to perform feats with it the Covenant never even thought of trying. While she was in control of that ship, Cortana was also able to act as the Gettysburg's AI at the same time, albeit while the ships are linked and is able to transfer herself from one ship to the other at will.

"Cloning" and Fragmenting
Another of her abilities was the ability to clone herself. She got this from a Covenant AI she destroyed and dissected. She first tested it by copying her language translation abilities and found it worked great. She also could seem to sense what progress the clone had made as if she retained a connection to it. Later, due to the importance of her getting to Earth due to all of the data she'd collected on Halo, the Flood and Covenant technology, she was forbidden from going on John-117's mission, but she was able to make a clone of her infiltration abilities to give John enough of her capabilities to infiltrate the Covenant command and control station. She claimed that this would not be a complete copy, but she thought that what it was would be enough. The clone had at least some of her personality as well. The clone retained her abilities to hack systems and some limited mission planning routines that allowed her to make basic plans to help the Spartans, but was unable to make the complicated plans that Cortana could come up with. The original clone made a copy of itself into the station's systems to help out and, due to being overwhelmed by Covenant security AIs, ended up making hundreds of copies of itself which overwhelmed the system and made accomplishing anything hard for the clones as they began to lose their coherent state, but still could control the system. The original clone was left behind in the reactor system. It was placed there to overload the reactors and was never removed once it started the process. All of the clones created on the mission were destroyed when the station blew, but provided invaluable help to the Spartan team. Later, while held captive by the Gravemind, Cortana used her cloning ability to create data-stripped clones of herself and ones of her lower-priority functions to distract the Gravemind. These were all consumed by the Gravemind, but they helped buy Cortana time and one also helped her create her message to John-117. Some were even responsible for the more rampant parts of two of the Cortana Moments. During Halo 4, while on The Didact's ship, she creates multiple clones of herself through Rampancy to help overwhelm the ship's defenses and lower the Composers shields for John to plant the HAVOK nuclear mine to destroy it with. Cortana and her clones later manifest themselves as hard light to aid John in battle by tying down The Didact so he could plant a Forerunner Grenade to his chest to stun him so he would fall into the event horizon of the Composers energy network.

Other Abilities
She was also very good at planning missions for John, including the destruction of Halo. In Halo: The Flood, John comments that he's not sure who's better at blowing things up: him or her. It was also her plan that led to the destruction of all of the Flood that had escaped Installation 05 and saved the galaxy from a further Flood invasion. Apparently, she has mission-planning routines that help her with this as her clone told John that a copy had only limited-mission-planning routines and was only able to help the Spartans form basic plans.

Another ability that she developed was a limited, teleportation ability on Installation 04. She learned how to teleport on Halo while in its control systems, but as she couldn't access Halo's power grid, she couldn't perform this task very often. She did teleport once with John-117 by drawing power from his fusion pack, saying that she was sure it wouldn't cause permanent damage to his power pack or shields, but both agreed that this should only be done once. She learned where they needed to go from the Covenant Battlenet and teleported them there although they ended up upside down due to her not getting the coordinates completely right. She has not used this ability since although she could presumably use it on any Halo but would have the same power requirements problem.

Trivia

 * Cortana is usually voiced by Jen Taylor, who also voices Catherine Halsey. In Halo Legends, Shelley Calene-Black voices both Halsey and Cortana.
 * In Halo 4, Cortana's face was modeled after international model Paisha Coffey and her body, after Frances Ingraham and Katrina Le. Her movement was performed by Mackenzie Mason using motion capture technology.
 * Easter eggs involving Cortana can be found in a couple places. In Halo 3, look for a UNSC mobile computer. Watch the lower-left monitor. After a few seconds, Cortana's face will appear for an instant and then disappear. Two of the easiest ways to see this is to either look at the aforementioned screen in the beginning of Crow's Nest, or at one of the computers in the multiplayer map High Ground.
 * There was going to be an alternate story in Halo: Combat Evolved in which John-117 rediscovered Cortana inside the control room and she had become mad with power, wanted to take over Installation 04 and ultimately, the universe.
 * In the original draft of the Halo: Combat Evolved script, Cortana was supposed to have an accent akin to the British Isles. When in search of voice actors, Martin O'Donnell made sure they had the ability to interpret the accent correctly. This is evidenced by the fact that in Halo: Combat Evolved, Cortana uses several British idioms, such as "Sod off!" when addressing 343 Guilty Spark.
 * She was rated as one of the ten most disturbingly sexual game characters by Games.net and one of the fifty greatest female video game characters ever by Tom's Games.
 * In Halo 3, she repeated lines Dr. Halsey has said before such as "You will be the protector of Earth and all her colonies." which Dr. Halsey says to the 6- year- old Spartans in Halo: The Fall of Reach. Cortana also recites a few lines from the Cortana Letters in Halo 3 in some of her messages and in the announcement trailer. Some of the lines are said in the Cortana moments in the level Cortana. At certain points in the Halo 4 campaign, Cortana during moments of rampancy is identified on John-117's HUD as Dr. Halsey and often repeats Halsey's quotes.
 * Cortana had many similarities to the Marathon AI, Leela, such as control over certain functions of ships and other locations in their computer systems.
 * Being a smart AI, Cortana's operational life span was approximately seven years. However, after she took in all the Forerunner information in Halo's control room, her estimated life span was possibly halved, due to the vast task of storing, processing etc. all that information. In addition, all of the data she absorbed on Halo noticeably decreased her efficiency.
 * The name Cortana (also Curtana or Courtain) is a Latinized form of the Anglo-French curtein, from Latin curtus meaning "shortened." The name is used for a ceremonial type of sword. According to legend, one such weapon was the sword of Ogier the Dane - it bore the inscription "My name is Cortana, of the same steel and temper as Joyeuse and Durendal." Durendal (spelled 'Durandal' in this sense) was the name of an Artificial intelligence in a previous Bungie game, Marathon. This also ties in with Cortana telling John "I am your shield, I am your sword."
 * In Halo: Glasslands, The smart AI "BB" sees Cortana as a negative role model. He believes she has become far too human after spending so much time around them.
 * In Halo: Combat Evolved Anniversary, Cortana takes her Halo 3 form. In the game, Cortana always remains in a blue color, unlike the original, where she is seen in a purple color, and changes to a green color when in Installation 04's control center.
 * On the level Requiem, an audio log can be found in which Dr. Halsey mentions how Cortana could possibly outlive the 7-year life expectancy before saying how odd it is for a UNSC AI. While she did outlast the 7-year period, she performed poorly afterwards.
 * Jen Taylor was awarded "Performance of the Year (Female)" by Ben of "TheGamerDrive," for her performance in Halo 4.
 * The Didact seemed to show some interest in Cortana, perhaps because of how advanced Cortana was considering humanity and its lower than expected technological sophistication.
 * Cortana was chosen to be the name for the personal assistant in Windows Phone 8.1 and Windows 10. The name was originally "a code name to rally the team around what they were building," but the decision to keep the name was made as a result of petitions and polls asking for the name to be kept when the code name was leaked.