The skin is the human body's first defense system. It usually prevents microorganisms in the environment from entering the human body. But when there is a wound on the skin, microorganisms will enter through the wound and cause skin infection. Abrasions, also called cuts or "brush burns," refer to mild injuries that occur when the skin is rubbed or torn. It is a shallow wound that usually wears the top layer of the skin (the epidermis) due to friction applied to the body. The scraped surface layer of the skin caused by abrasions may contain dust particles. If not cleaned and maintained, it may cause dermal infections or other complications.