A muscle is the tough, elastic tissue that makes our body parts move. Muscles are found throughout the body. As a person grows, the muscles also get bigger. Muscle makes up nearly half the body weight of an adult.
The human body has more than 600 major muscles and about 240 of them have specific names. There are two main types of muscles: skeletal muscles and smooth muscles. A third kind of muscle, called cardiac muscle, has characteristics of both skeletal and smooth muscles. It is found only in the heart.
The largest muscle in the human body is called the gluteus maximus and this is situated in the buttock, while the smallest muscle is the stapedius which can be found in the middle ear.