Chan (ちゃん?) is a diminutive suffix; it expresses that the speaker finds a person endearing. In general, chan is used for babies, young children, grandparents and teenagers. It may also be used towards cute animals, lovers, close friends, any youthful woman, or between friends. Using chan with a superior's name is considered to be condescending and rude.
Although, traditionally, honorifics are not applied to oneself, some young women adopt the childish affectation of referring to themselves in the third person using chan (childish because it suggests that one has not learned to distinguish between names used for self and names used by others). For example, a young woman named Kanako might call herself Kanako-chan rather than using a first person pronoun. Also, the very common female name suffix -ko (〜子) may be dropped, as in Kana-chan.