Hemiplegia is a state in which half part of a body is paralyzed. Hemiplegia is more serious condition than hemiparesis, in which half part of the body is weaken but not paralyzed. Hemiplegia may be inherited, inborn or get from some sickness or stroke. Hemiplegia or Paralysis is the loss of the control to move a part of the body because of injury or illness of the nerves that provide the muscles involved in moving that portion of the body.
The main points in this description are initially that, paralysis or Hemiplegia refers to loss of movement of affected part rather than only weakness, and secondly that the trouble is not directly of the muscles but it begins in the nerves to the muscles. Occasionally paralysis is also due to diseases of the muscles rather than the nerves.
When only one part of body is involved in the situation, then it is referred as as monoplegia. If the arm and leg on the similar side of the body are affected the word used is hemiplegia. When both legs are paralyzed it is known to as paraplegia. Paralysis of all four limbs is generally known as quadriplegia/paresis, or sometime diplegia.