A nuc (nucleous hive) is a small hive. It can hold anywheres from 2 to 8 frames in a super that is reduced in size to enable the bees to keep warm. They have numerous uses. they can hold a swrm if captured. Often used to aid in swarm prevention, banking queens, starting a hive from a split, aiding in an apiary by having backup queens.The list goes on. Basically, its a starter hive.