Joinery is a part of woodworking that involves joining together pieces of wood, to create furniture, structures, toys, and other items. Some wood joints employ fasteners, bindings, or adhesives, while others use only wood elements. The characteristics of wooden joints – strength, flexibility, toughness,appearance, etc. – derive from the properties of the joining materials and from how they are used in the joints.
The eight basic types of joints are: butt, dado, rabbet, lap, dovetail, mortise and tendon, miter, and tongue and groove.
The Butt Joint is an easy woodworking joint. It joins two pieces of wood by merely butting them together. The butt joint is the simplest joint to make. It is also the weakest joint unless you use some form of reinforcement. It depends upon glue alone to hold it together.
A biscuit joint is nothing more than a reinforced Butt joint. The biscuit is an oval-shaped piece. Typically, a biscuit is made of dried and compressed wood, such as beech. You install it in matching mortises in both pieces of the joint.
A dovetail joint is created by cutting a series of triangular-shaped sections (called tails) from the end of one piece of wood and matching sections (called pins) from the other piece of wood. The tails and pins interlock to form a strong 90-degree joint. Dovetail joints are technically complex and are often used to create drawer boxes for furniture.
Through mortise and tenon – To form this joint, a round or square hole (called a mortise) is cut through the side of one piece of wood. The end of the other piece of wood is cut to have a projection (the tenon) that matches the mortise. The tenon is placed into the mortise, projecting out from the other side of the wood. A wedge is hammered into a hole in the tenon. The wedge keeps the tenon from sliding out of the mortise.