She is a full-body cyborg employed as the squad leader of Public Security Section 9 in Ghost in the Shell . Her various incarnations in the manga, movies, and TV series all portray her differently.
Since each of these has an independent storyline, Kusanagi's physical and mental characteristics have been modified in different ways to reflect the focus of each respective story.

Known to her colleagues as "The Major", Kusanagi is a highly skilled operative with an playful, though introspective and philosophical personality. Little is known of her early history, though the television series hints at some of her background, usually through flashbacks and commonly from the points of view of others, rarely from her own.

At the end of the series Kusanagi confessed that she couldn't remember what her real name was, indicating that Motoko Kusanagi is actually only a pseudonym.

Source:Wikipedia