Particle board, also known as particleboard and chipboard, is a wood product made from chips of wood or sawdust. It is mixed with resin or glue (both adhesives), then, under pressure and heat, pressed into uniform sheets. Particle board is used in building construction and furniture making. It is cheaper to make than plywood but not as strong. Type 1 particle board when exposed to moisture. For that reason it is not usually recommended to be used outdoors. Type 2 particle board uses waterproof glues and can be used outdoors.