The thorax or chest (from the Greek θώραξ thorax "breastplate, cuirass, corslet" via ) is a part of the anatomy of humans and various other animals located between the neck and the abdomen. The thorax includes the thoracic cavity and the thoracic wall. It contains organs including the heart, lungs and thymus gland, as well as muscles and various other internal structures. Many diseases may affect the chest, and one of the most common symptoms is chest pain.