This document provides information about muscle origins and insertions. It defines origin as the attachment of a muscle tendon to a stationary bone, and insertion as the attachment to a moving bone. Examples are given of the origin and insertion points for several muscles like the bicep, gastrocnemius, and hamstrings. A table identifies the origin and insertion of additional muscles. The document also discusses antagonistic muscle pairs, with agonists being prime movers that contract to cause movement, and antagonists relaxing to allow movement. Examples of muscle pairings for motions like elbow flexion are provided.