Evil laughter
this is simply evil laughter...it is funny but has no real purpose. Often used in movies the ever so popular mwahahaha is a clever sign that the evil master is going to do something bad...this is also my favorite thing to say MWAHAHAHAHAHA!!!!!
Evil laughter is currently used in media as comic relief as a parody of earlier media. Socially it is used in a playful manner when an individual is being mischievous or up to no good.