All drumset shells are made by layering thin sheets of wood (called plys) 1 to 1.5 millimeters thick and gluing them together to get a certain thickness, usually between 6 and 9 plys total. They are then either stained, lacquered, or wrapped with a covering to give them their visual appearance. Lugs are mounted on the shells to hold the rims and heads to the drum.
Much debate surrounds what the best wood and number of plys is for a drum. For the most part, after you get into the semiprofessional level and above, shell composition becomes a matter of personal preference. Ultimately, you choose based upon the type of sound you want.
They types of wood that you can find consist of maple, birch, beech, mahogany, gum, and the undisclosed iall woodi variety. Each type has its own timbral characteristics. For instance, maple has a louder, brighter sound than birch, while birch has a mellower tone that has a wetter (thicker) quality to it. Each can sound great if tuned properly.