A wall cabinet refers to the parts of a cabinet set that are installed over the countertop, in contrast with the wall cabinets. Together, the wall cabinets and base cabinets will make up the main parts of a kitchen cabinetry set. Wall cabinets often used to store dishes, cups and glasses, and other items in a kitchen design that are set up above the waist level. They are usually 12 inches deep, which is somewhat shallower than the base cabinet counterparts.