The term for a group of fish swimming together is a "school." Schools can vary in size from just a few fish to thousands, providing various benefits like protection from predators and improved foraging efficiency. Fish in schools often exhibit synchronized swimming behaviors, which can confuse predators and increase safety. This social interaction is crucial for many species, as it helps them thrive in their environments. The concept of schooling is not limited to fish; it can also apply to other aquatic animals, such as shrimp or squid, that exhibit similar group behavior for survival and feeding.