A pronoun takes the place of a noun in referring to a person, a place, a thing, or an idea. Pronouns can be personal, relative, demonstrative, interrogative, indefinite, reciprocal, or reflexive.
Personal Pronouns: I, you, we
Relative Pronouns: that, which
Demonstrative pronouns: this, that
Interrogative Pronouns: who, what
Indefinite Pronouns: somebody, nothing
Reciprocal Pronoun: each other
Reflexive Pronouns: herself, yourself