They could be cause by a few things. It could be a bug bite. If you itched it, then bumps could form even more. It could also be an allergic reaction to something. (Hives, possibly. Even just on a small, isolated area, it can happen.) If it is part of a rash, it might be something like poison ivy or poison oak. It could be some ingrown hairs, depending on the area. You best bet - since it's itchy - would be a bug bite or reaction. Try a soothing, anti-itch cream. If you aren't sure or are concerned, see ac doctor. They could probably help.
Chickenpox causes widespread bumps, not clustered. Shingles or poison ivy are just a couple of problems that can cause a cluster of itchy bumps. See your health care provider for definite diagnosis and treatment.
excezma (cant spell it)
it's called heat rash
scabies
pimples.
warts
Could be shingles. Could be shingles. Could be shingles.
It's a rash.
Dysnidrosis
A diagnosis cannot be made from a description. See a doctor. It sounds like it may be heat bumps or sweat bumps. I believe it may also have to do with thighs rubbing together that makes bumps. I was told it could be HPV
probably hives - allergic reaction to something - very itchy - treat with calamine or such or chicken pox - see your GP
you got something. go to the docter