Musculus pectoralis refers to the chest muscles located in the upper torso region. However, there are various synonyms that can be used interchangeably with this term. Some of these include the pecs, chest muscles, pectoral muscles, or simply chest. The pectoralis major is the larger muscle group, while the pectoralis minor is a smaller muscle located underneath it. The pecs are responsible for several movements, including shoulder flexion and rotation, arm adduction, and internal rotation. They are commonly targeted in resistance training exercises, including push-ups, bench press, and flyes. Overall, the chest muscles play an essential role in upper body strength and aesthetics.