Veneer is this sheets or leaves or wood (0.3 to 6 mm), which are cut from the trunk or log by sawing, slicing or peeling. They are then glued onto a substrate. Substrate materials can be particleboard, MDF boards (= medium density fibreboards), multiplex boards or plywood.
Veneer is one of the finest things that can be made from wood. In previous ages, only kings, members of the nobility and rich members of society could afford veneered furniture. Today real wood is affordable for everyone.