A Collective Noun names a group of specific things, animals or people with a singular form. It denotes such group as a single entity.
Collective nouns can be either singular or plural, depending on context.

People: audience, crowd, jury, family, group, nation, staff, cast, gang, team

Animals: flock, colony, swarm, gaggle, herd

Things: bunch, bundle, set, stack, cache, batch, bouquet