Chemically what is body odor?

Chemically what is body odor, primarily? Does Propionic acid have an odor?
I vaguely recall buteric acid does have an odor. Is that correct?

I think buteric acid has an odor we like in cheese but find repulsive in vomit.

IIRC if you read up on how mosquitos find targets, there is much information on the chemicals in human body odor that draw them.

both those acids stink and are part of body odor.