The main aim when jointing any pieces of timber together should be to cut the joints and arrange them so as to weaken the pieces of timber as little as possible. When the connection is effected entirely by means of timbers fitted together, it is called a joint. Most commonly, however, the joint is strengthened and secured by fastenings, such as: wedges, glue, draw pins, pins, screws, nails, etc. In nearly all cases simple joints are more effective than complicated joints.

Woodworking joints can be divided into three main classifications that correspond to their functions: joints in length for increasing the lengths of timber, joints in width for increasing the width of timber and angle joints.