The Extensor Pollicis is a muscle located in the forearm that plays a crucial role in thumb movement. It is part of the group of muscles known as the extensor muscles, which are responsible for extending various parts of the hand and fingers. Specifically, the Extensor Pollicis helps extend the thumb at the metacarpophalangeal and interphalangeal joints, allowing for a wide range of thumb motions. This muscle has two distinct parts: the Extensor Pollicis Longus and the Extensor Pollicis Brevis. The Longus extends the thumb at the distal joint, while the Brevis extends it at the proximal joint. Proper functioning of the Extensor Pollicis is essential for activities that require thumb dexterity, such as grasping objects and using tools.