Motivation is an integral part of human behavior. It is an important determinant in why a person may pursue a particular activity. Intrinsic motivation is something internal, either primal (such as the need to eat) or learned (such as the knowledge of healthful eating). Extrinsic motivation is something external and may be both positive (such as rewards) or negative (such as punishment). Repeated exposure to extrinsic motivation may help create an intrinsic motivation. For example, students who are motivated to learn to receive good grades may develop a desire to learn.