Is called an indefinite pronoun

An indefinite pronoun is a Word that takes the place of a noun (or noun phrase) that is an unknown or unnamed person, thing, or amount.

The indefinite pronouns are: all, another, any, anybody, anyone, anything, both, each, either, enough, everybody, everyone, everything, few, fewer, less, little, many, more, most, much, neither, nobody, no one, nothing, none, one, other, others, several, some, somebody, someone, something, such, and they (people in general).

Example sentences:

• Shh, I just heard something.
• Everyone has left the building but many are still waiting for their ride.
• We invited five people but none have arrived yet.
• I've received several replies.
• All is forgiven.