The earlobe, also called the lobule, is the fleshy lower part of the outer ear that hangs down and is designed to collect sound waves from the air and guide them to the tympanic membrane, more commonly called the eardrum. The vibration of the eardrum sends sound waves down into the inner ear, where these sounds are processed by delicate sensory organs and then processed by the brain.
The outer ear is called the pinna, or the auricle. The human outer ear is not designed as efficiently as the ears of most other animals, so humans do not hear as well. In humans, the auricle is rather rudimentary, attached flat against the side of the head and connected by small ligaments and muscles. It is composed mostly of fibrocartilage, molded into ridges and furrows and covered by skin. The shape of the ear is designed to optimize hearing.
The eardrum is the only part of the outer ear that contains no cartilage. It is mostly composed of fatty tissues. The outer ear also has some elementary muscles. In most cases, these ear muscles do not have any ability to move, although some people have learned to voluntarily initiate limited movement of their ears.