Dopamine is a neurotransmitter. Many different kinds of animals and humans use it to transmit information. It is used when the brain sends signals to the muscles in the body to make them move. It can make a person feel happy.
Dopamine is an important chemical found in the brain. If the brain does not make enough dopamine, it causes an illness called Parkinson's disease. This can be treated by giving the Parkinson's disease patient a drug called L-Dopa, which the body converts to dopamine.