The Major was created by renowned manga scribe, Masamune Shirow.
Motoko Kusanagi, often referred to by the codename "The Major", is the commanding officer of her squad in Public Security Section 9, an intelligence department which operates under the authority of the Japanese Ministry of Home Affairs. Section 9 operates in Niihama-Shi (New Port City) but its exact headquaters are top secret. Their mandate is to investigate cyber-crimes, and respond to technology based threats and terrorism. The Major has been involved in several high profile cases involving the likes of the Puppeteer, the Laughing Man, and the Individual Eleven.
The Major is a bit of a mystery. She tends to keep her human emotions well under control, and what remains of her personal life she mostly keeps to herself. What is known is that she was involved in a near-fatal plane crash when she was only a child. As a result, she underwent full cyberization at the age of nine with the only organic part of her remaining being a portion of her brain. She also initially had trouble adapting to the use of her new body and inadvertently broke one of her favorite toys, a doll. This incident was one of the only times that Motoko was shown capable of crying.
Later, Motoko became an elite forces squad leader and an expert in electronic warfare after years of intense training. It was as the leader of a covert-ops squad operating through Section 9 that she first met Chief Aramaki who recruited her. Ishikawa and Batou (with whom she would seem to develop mutual feelings of attraction) may have served with her in the past during their tour of duty in the military. Other new recruits under Kusanagi's command include Togusa, Pazu, Borma and Saito.
As stated, she often goes by the title "Major", but this may not be a formal rank. It is not yet known if Motoko held the rank of Major during her service with Japan's conventional military forces before becoming a covert-ops agent with Section 9 (which would explain why ex-military agents like Batou use the title when referring to her), or if the title evolved out of recognition for the leadership position she holds within her squad.
In the animated film series that was inspired by the Ghost in the Shell manga, Kusanagi fused with the "Puppet Master", codenamed Project 2501, and left Section 9. In the anime series she continues to lead the squad against various acts of cyber-terrorism, such as the cases involving the 'Laughing Man', the 'Individual Eleven', and the 'Puppeteer'.
The depiction of Motoko Kusanagi's character is distinctly different from one version to the next, as each Ghost in the Shell adaption (the manga series, the movie series, and Stand Alone Complex TV series) follows a different time-line. In the original manga, The Major was a spunky and sometimes irreverant individual who nonetheless demonstrated a commending presence while on duty. In the film series she was portrayed as a more contemplative person with a sometimes brooding demeanor. This was a reflection of her tendency to question her own humanity and whether or not she had a soul (what cyborgs refer to as their "ghost"), a character trait that the film creators wished to emphasize. The anime series, Stand Alone Complex, and the film it inspired (Solid State Society) restored some of the humor to the character from the original manga that was lacking in the other film adaptions.
It has been suggested that Kusanagi may be lesbian since she has been intimate with other female cyborgs. This is common in part because of the high degree of compatibility with cybernetic devices in cyborgs of the same sex. It is much more likely however that the Major is bisexual as she has had boyfriends, and seems to have feelings for fellow Section 9 operative, Batou. Batou will also at times call her by her first name, Motoko, instead of using her title, which suggests he shares her feelings.
Lastly, Motoko is known for her provacative dress and attire (or lack of attire). And she will at times experiment with what others may deem "human vices" in an attempt to understand that part of her humanity, and in particular her femininity.
Motoko Kusanagi posseses an incredibly durable prosthetic body, with enhanced strength, speed and coordination. In fact, only part of her brain and spinal cord remain composed of human tissue. The cybernetic implants in her brain provide her with extraordinary hacking capabilities which she uses to hack into computer databases, and even other cyber-brains (a process known as ghost-hacking).
The Major is often regarded as the most powerful and dangerous agent of Section 9. She has extensive combat experience, is unusually intelligent, is an accomplished leader, and an expert in the martial arts. She also uses "therm-optic" camouflage to render herself invisible, giving her a tremendous advantage whenever stealth is required.
Film - Ghost in the Shell and Ghost in the Shell: Innocence
Motoko Kusanagi as seen in the first GitS film
This version of Motoko Kusanagi is far more subdued in terms of personality, to the point of brooding, but no less effective as a leader than her Manga counterpart. Throughout the first film she seems distant and detached as she is preoccupied by a rash of cyber-crimes instigated by the so called "Puppet Master" (Project 2501). The film focuses on her inner struggle to come to terms with her own nature, whether or not she has a "ghost" or if she has lost her humanity to the machine, and what it all portends for the nature of humanity in a world in which mankind and technology are becoming ever more inextricably linked.
Motoko has a much smaller presence in the sequel, Innocence, although she does appear in the film in a supporting role while aiding former partners Batou and Togusa.
TV Series Film - Ghost in the Shell: Stand Alone Complex and Ghost in the Shell: SAC: Solid State Society
In Stand Alone Complex, Motoko resembles her manga-self much more than in the films, although her banter-y relationship with Chief Aramaki isn't seen. Some fans have come to the conclusion that Motoko may be bisexual due to the content of several episodes combined with the rarity of her close relationships with men. This is also true of her Manga incarnation as mentioned earlier. Throughout the series however, Motoko and Batou seem to develop a closeness, as do Motoko and Hideo Kuze. During the series Kusanagi is also sometimes seen taking on the identity of "Chroma" while she is in the cyber-world, before returning to her real body. After the death of Kuze at the end of the second season, Motoko retires from Section 9 and practically disappears for a time. She is seen again in the film Solid State Society when the actions of the Puppeteer bring her and Section 9 (both conducting their own investigations) together again.