I stole this from my other blog, hope it helps

Reinforcers & Punishers
What we know from studying behavior is that it is usually predictable and we behave the way we do because of a past history of reinforcement or punishment. For example your child might throw a tantrum to gain access to reinforcers (lets say candy) due to a past history of you (or someone else) giving your child candy for crying. It happens everyday. Another example might be that you do not put demands on your child while he is watching TV because in the past he has screamed and hit when you did. Your behavior was punished in the past and as a result you no longer do it. You may ask for a kiss from your spouse because in the past they kissed you and therefore reinforcing your "asking for a kiss" behavior. The examples are endless.