It happens to everyone; we all get angry and have to release tension somehow. One way of doing this is through hostile aggression. This is anger-motivated aggression that serves no purpose but to let off steam. Some people do this by punching their pillow, crying, or yelling. They know that doing these things won’t achieve anything; it simply helps them in coping with their anger. The boy in the following clip is the perfect demonstration of hostile aggression.
This boy is obviously experiencing large amounts of aggression. Rather than do something constructive with this aggression (instrumental aggression) he lashes out in a fit of punching, yelling, and thrashing. He knows that all of this movement is not going to get his mom to give him his video games back, but he does it regardless. As we see by the end of the video, all of this “letting off steam” seems to have helped calm him down.