Hernia represents a bulge that comes through the openings of the muscle or tissue that surrounds it.
In other words, hernia consists of a part of an organ that comes through the weaker areas of the muscles or tissue that surrounds it. For example, a part of an organ, that is breaking out through an opening in the muscle or the tissue that maintains it on position.
Normally, hernias are referred to the abdominal area, as the limits are the chest (in the upper part) and the hip (in the lower part).
Hernias are not harmful, usually, but they are not going to heal by themselves. It is indicated to see a doctor as soon as the bulge occurs.
Hernias can occur in different parts of the body. Each type of hernia is actually differentiated by the area of appearance: