Beyin is the Turkish word for "brain," which is the central organ of the nervous system in humans and many animals. It is responsible for processing sensory information, controlling movements, and regulating bodily functions. The brain is made up of billions of neurons that communicate with each other to perform complex tasks. The brain is divided into several regions, each with specific functions. For example, the cerebrum is involved in thinking and decision-making, while the cerebellum coordinates movement and balance. Overall, the brain plays a crucial role in shaping behavior, emotions, and cognitive abilities.