The interphalangeal joints are the hinge joints located between the phalanges, or bones of the fingers and toes. These joints allow for bending and straightening movements, enabling actions like gripping and walking. Each finger has two interphalangeal joints, while the big toe has one. These joints are classified into two types: the proximal interphalangeal (PIP) joints and the distal interphalangeal (DIP) joints. The PIP joints are found between the first and second phalanges, while the DIP joints are between the second and third phalanges. Proper functioning of the interphalangeal joints is essential for hand and foot mobility.