The Triceps are the muscles located on the back of the upper arms, and oppose the biceps located at the front of the arms.
There are three parts to the tricep muscle: the long, medial and the lateral 'heads'.
Triceps means 'three heads'-i.e. there are three points of origin.
The triceps extend the elbows and is used in any movement or exercise where the arm is straightened, such as press-ups, punching, and overhead lifting.
The triceps originates from both the shoulder and the top of the humerus, and inserts on the ulna of the forearm.