how come when u sweat...?

Question

like u sweat in all places on ur body but is the sweat in ur armpits the only type that smells bad(causing b.o)

Answer 1

It's bacteria that causes odor. Bacteria will grow in warm and moist places. Armpits, when they sweat, are a bacteria's dream. So are crotches.
Also, bacteria sticks to hair, so you really want to keep your body hair clean to help avoid the odor.

Answer 2

Bacteria on the skin. Other types smell too, esp. down there if you know what I mean. Other places you sweat might not sweat as much as the pits, which is why they don't interact with the bacteria as much.