A dado joint is a woodworking joint that connects two pieces of wood at a right angle. It is created by cutting a groove, or dado, into one piece of wood, allowing the other piece to fit snugly into it. This type of joint is commonly used in furniture making and cabinetry, providing strength and stability to the structure. Dado joints can be made using various tools, such as a table saw, router, or chisel. They are often used in the construction of shelves, where the shelf fits into the dado cut in the side panels, ensuring that it remains securely in place.