Furniture makers are essentially concerned with two things: shaping and joining wood - everything else is just decoration. The most beautifully carved table will simply fall apart with shoddy joinery.
The illustrations below are of a variety of joint called "housed" indicating that one part of the joint is captured or surrounded by another. I've drawn four basic joints in their simplest forms. There are hundreds of variations of and applications for each. Nobody knows exactly when these joints were invented, but they've certainly been in use for several thousand years, in cultures all around the world.
It is deeply satisfying to cut and assemble a finely crafted joint.
Dovetail
The dovetail joint is most often associated with drawers, but it's useful in many applications. The variety shown here is called a "through dovetail". Another popular variety is the "half-blind", commonly used in drawer and carcass construction.
Half-lap
The half-lap joint is used to join intersecting frame members at a given point along their lengths. Builders of Japanese shoji screens make extensive use of complex half-lap joints, often joining six members at one point. It's humbling to look upon such a beautiful joint.
Mortise and Tenon
The mortise and tenon joint is used to join the end of one frame member to a point along the length of another. They are widely used in table, chair, and cabinet construction. The example below is a pegged mortise and tenon - the joint will stay together without the use of adhesives. Timber framed houses make extensive use of this variety.
Dado (pronounced "day-doe")
Dado joints are commonly used to join intersecting panels or wide boards.
