WEDGES are pieces of material, usually metal or wood, that are used to secure objects in place. INSERTS are pieces of material that are inserted into an object to fill a gap or provide support. SHIMS are thin pieces of material, often metal or plastic, that are used to fill small gaps between two objects. CHOCKS are wedges that are used to prevent an object from moving. All of these terms refer to wedges, which are used to secure objects in place and prevent them from moving.