Smiling, joking, and giggling; some of our most joyful moments can be
explained by how laughter affects our health. Some people have loud,
contagious laughs, some snort, and some titter daintily and cover their
mouths.
In the body, laughter is nothing more than a repeated contraction of the
diaphragm, located below the lungs. You might laugh at a joke or a funny memory
or watching someone fall down on a funny video. These are external stimuli that
cause you to react with humor.
