They may be fibromas. Harmless. Move one around; if it is loose under the skin, it is probably just a fluid filled cyst. If it seems stuck in place but still noticeable, it probably has "tentacles" and is attached to surrounding tissue. To be sure, go to a dermatologist. If you have the removed and they are just fibrous cysts, you'll have scars, and then more cysts in the future. Some people are just prone to them.