Answer:
Collective nouns are words used to for a group of something such as a crew of workers, a chain of restaurants, or a litter of kittens.
Plural nouns are words for more than on person, place, thing, or idea such as a worker or two workers; one restaurant or three restaurants; and a kitten or four kittens.
Collective nouns can be singular or plural; for example, two crews of workers, several chains of restaurants, or the mother has had two litters of kittens.