The musculoskeletal system is a vital organ system composed of two main components: the muscle system and the skeleton. The muscle system includes three types of muscle: skeletal, cardiac, and smooth muscle. Each type has unique characteristics, but all muscles share the ability to contract, which is facilitated by the interaction between two proteins, actin and myosin. Muscle cells, known as myocytes, are specialized for contraction, and the prefix "myo" typically indicates a relation to muscles.

In the human body, the muscle system works in conjunction with the skeleton to enable movement, known as locomotion. The skeleton serves as the support structure, and in humans, it is classified as an endoskeleton, which is an internal framework made of mineralized tissues such as bone. This rigid structure provides support and protection for internal organs while allowing for a range of movements when connected to muscles.

In contrast, some organisms, like arthropods, possess an external skeleton, or exoskeleton, which serves a similar protective and supportive function. The connection between muscles and bones is crucial for voluntary movement, allowing for dynamic actions such as running, jumping, and other forms of locomotion, exemplified by the swift movements of a cheetah.