In its normal use the English expression "self" is not even quite a word, but something that makes an ordinary object pronoun into a reflexive one (e.g., her into herself). The reflexive pronoun is used when the object of an action or attitude is the same as the subject of that action or attitude. If I say Mark Twain shot himself in the foot, I describe Mark Twain not only as the shooter but as the person shot. In this sense "the self" is just the person doing the action or holding the attitude that is somehow in question. "Self" is also used as a prefix for names of activities and attitudes, identifying the special case where the object is the same as the agent: self-love, self-hatred, self-abuse, self-promotion, self-knowledge.

"The self" often means more than this, however. In psychology it is often used for that set...