The pronouns she, he, it, and I are singular.

The pronouns they and we are plural.

The pronoun you can be singular and plural.

She refers to a female.

He refers to a male.

It refers to a thing, an animal, or an idea.

I refers to oneself.

We refers to more than one person including the speaker.

They refers to more than one person, place, or thing excluding the speaker.

You refers to a person or persons spoken to.