A group of sheep is commonly called a flock.
In general, a group of sheep is referred to as a flock, but there are also some more specific terms that can be used depending on the context. For example, a group of domestic sheep that are kept together for breeding purposes is called a band or a mob. A group of sheep that are herded together for grazing is sometimes called a drift or a drove.
Sheep are social animals that tend to form tight-knit groups, with a strong hierarchy and a clear dominance order among the members of the flock. Sheep are known for their herding instinct, and they tend to stick together in groups for protection from predators, as well as for warmth and social interaction.
In addition to their social behavior, sheep also have some interesting biological adaptations that help them survive as a group. For example, their wool provides insulation from the cold, and their hooves are designed to grip the ground, making it easier for them to navigate steep or rocky terrain.