Comic relief.

1.What is the comic relief?

Comic relief usually means a releasing of emotional or other tension resulting from a comic episode interposed in the midst of serious or tragic elements in a drama. 

2.Why is it often used in horror films?

A sidekick used for comic relief will usually comment on the absurdity of the hero's situation and make comments that would be inappropriate for a character who is to be taken seriously. Other characters may use comic relief as a means to irritate others or keep themselves confident.

3.Do you remember laughing in horror films? Can you think of an example? 

Yes, Scary Movie.