what are bruises
Bruises Overview. A bruise is a common skin discoloration that results from the breakage of tiny blood vessels leaking under the skin after a traumatic injury. Blood from damaged blood vessels beneath the skin collects near the surface of the skin to appear as what we recognize as a black and blue mark.This mark is from skin discoloration by red blood cells and their contents. A bruise is also known as a contusion.lood from damaged blood vessels beneath the skin collects near the surface of the skin to appear as what we recognize as a black and blue mark. This mark is from skin discoloration by red blood cells and their contents. A bruise is also known as a contusion.