In a perfect world, you wouldn't need to worry about discipline, but all parents face situations that require intervention. The goal of discipline is to decrease the undesirable behaviors and increase the positive choices your child makes. Both reinforcement and punishment are ways to achieve that goal, but the methods have subtle differences that may make one better suited for your child.
Reinforcement focuses on increasing the desired behaviors in your child. Your reinforcing action helps your child learn what you want him to do. Reinforcement is either positive or negative. In positive reinforcement, your child gets something positive for doing the right thing. You might praise him for helping his little sister tie her shoes or reward him with a trip to the ice cream shop for performing well on a test. Negative reinforcement might sound like punishment, but it is different. In this type of reinforcement, the child avoids something negative by making a positive behavior choice. He might avoid losing screen time privileges by getting his homework done, for example.
The motivating action or item should be something your child likes or enjoys. Using a toy he doesn't care about as a reinforcing item isn't likely to have an effect, for example. Tune in to your child's interests and the things that he values to determine the best motivators for his positive behaviors. Notice how he responds to actions, such as praise, to determine what is effective. The reinforcing action needs to take place immediately after the desired behavior to be effective. Using reinforcement often means ignoring minor negative behaviors in your child in favor of calling out the positive behaviors. When negative behaviors are severe - if someone is in danger or the action grossly ignores your family's values, for example - you may need to use a punishment technique to eliminate the behavior.
Punishment relies upon a negative stimulus to decrease undesired behaviors. While punishment often has a negative connotation, it doesn't have to be harmful if used correctly.Verbal reprimands is one such example. Extinction is a similar discipline method that takes away something the child likes or avoids giving a child positive reinforcement after misbehavior. Time-out and taking away belongings or privileges are two common types of extinction. Another example is ignoring a child after a minor misbehavior, such as throwing a temper tantrum, since the attention from an adult even negative attention is sometimes a reinforcing action.
Punishment should aim to teach acceptable behaviors, and not be used as a way to get revenge or inflict shame. Taking away privileges or using time-out are often considered more effective than spanking, especially over time. The consequence for the undesired behavior needs to have significance for the child. If using the extinction strategy, for example, you might take away your teen's driving privileges or cancel a play date for your child. For effectiveness, punishment should go along with rewards when your child behaves appropriately.