Applied behavior analysis
Primary reinforcers are reinforcers that fill a biological need. The four primary reinforcers are food, water, warmth and sex. Reinforcers that do not fill biological needs are called secondary reinforcers. Secondary reinforcers are not naturally reinforcing. A person needs to learn that they are reinforcing. They learn that they are reinforcing because they are paired with other things that are known to be reinforcing. They are also called conditioned reinforcers.