Blisters. We all hate them. "A blister is a small pocket of fluid within the upper layers of the skin, typically caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid called serum or plasma.[1] However, blisters can be filled with blood (known as blood blisters) or with pus (if they become infected)." (Wikipedia)
You usually get them on your hands or places where you get burns and what not. They are very painful (at least to me)
Right now I have 7 blisters covering my hands. I worked today shoveling 7,200Lbs of sand, and even with gloves on they got blisters.
My hands aren't soft either. They're pretty callust because I do a lot of weight lifting. But man do these things hurt.