What is the process for creating a keyed miter joint in woodworking?

To create a keyed miter joint in woodworking, first, cut the two pieces of wood at a 45-degree angle to create the miter joint. Next, cut a slot or groove in each piece where the joint will be, and then insert a key or spline into the slots to reinforce the joint. Finally, glue the pieces together and clamp them until the glue dries to complete the keyed miter joint.