Blisters are raised chambers full of fluid beneath the skin or between layers of skin. They can be caused by burns, second-degree freezing, and chemical corrosion. The most common cause, however, is physical friction such as when wearing new shoes, working in the garden, or performing other hard manual work. In these cases the upper layers of skin get separated from the lower ones, causing a hollow cavity which fills up with tissue fluid.
Blisters: painful and tiresome