The sound "baa" is commonly associated with sheep, particularly the domestic sheep species, known scientifically as Ovis aries. This vocalization is used by sheep to communicate with each other, signaling various emotions such as distress, hunger, or the need for attention from their flock. In addition to sheep, the "baa" sound can also be imitated by humans, often in children's games or educational settings to teach about farm animals. This sound is part of a broader category of animal vocalizations, which includes sounds made by other livestock like goats and cows.