Cardiac muscles found in heart are involuntary muscles that function throughout the life continuously without getting tired. These muscles are striated (have light-dark banding pattern), cylindrical and branched. They contract and relax rapidly in a rhythmic pattern to help in pumping of blood and work without fatigue.

Skeletal muscles are voluntary and they act according to our need i.e. they are under our control. Smooth muscles are involuntary muscles found in alimentary canal, urogenital ducts etc. They remain contracted for a long period of time.