Joinery is the heart of woodworking.
Joinery is what keeps our projects together.
Joinery can range from the use of nails to finely, handcrafted dovetails and everything other method in between.
If you are new to woodworking the many styles of joinery may seem overwhelming, but after you get a few projects under your belt it will all begin to make sense. For instance, you would not normally use the same joinery for a small box as you would for a table. The box would not be subject to the same stress that the table would, so the box joinery could be more delicate or ornate such as dovetails. The table joinery, on the other hand, would have to be robust to withstand everyday compression or tension that may be imposed on it.
Every project has its own unique joinery requirements. Joinery choices are not set in concrete. The woodworker has to choose the correct joinery to suit his or her project.
Think about a chair for a moment: The most important aspect of chair joinery is strength. I do not think you would want your chair to collapse when someone sits on it. Chair joinery has to withstand all of the stresses it may be subjected to. These include tension, compression, twisting and so on. This is all just common sense.