Final answer:
Livor Mortis is the postmortem change where blood pools in the lower parts of the body causing a purplish red discoloration of the skin, different from rigor mortis or decomposition.
Step-by-step explanation:
Livor Mortis is the formation of lividity on the skin after death. It is one of the recognizable signs of death, part of the postmortem changes that a body goes through. Essentially, it refers to the pooling of blood in the lower parts of the body due to gravity, which causes a purplish red discoloration of the skin. Livor Mortis is not to be confused with rigor mortis, which is the stiffening of muscles after death due to chemical changes within muscle fibers, or with the cooling of the body after death, known as algor mortis.
Nor is it the process of decomposition, which begins somewhat later after the other postmortem changes have set in. It is also different from phenomena like 'writer's cramp', which is caused by a temporary failure of the myosin heads to detach from the actin-binding sites in a living person, leading to muscle stiffness.