I'm sure there is an extremely in-depth psychological answer determined from many thousands of studies for this.
However, the simple answer is because they find it funny to humiliate/hurt/embarass others (depending on the situation).
UPDATE
Sometimes however, pranking is a friendly gesture between friends. A good example is the "Cream Pie" prank in Major League Baseball. When a player wins a game for his team and is interviewed for television afterwards, one of his teammates sneaks behind him and hits him in the face with a "Cream Pie" (which is usually shaving cream).
Most people who prank will prank all year long. However, some people who prank will only prank if they are not given treats at Halloween.
Prank Stars is a show to amuse. They made it to entertain people.
to prank people
Prank is way of fun. When they do that they are looking for fun to uplift themselves.
Look in the coments if people talk about a prank, don't watch the video.
No but when you prank call people have to right to call the cops on you
A war between two people pranking eachother, such as after they prank you, you prank them and so on and so on, in other words going back and forth
nop
you cant
i get pranky
It's annoying and potentially dangerous or damaging.
Depends on which country you are in.