To create blockboard, wooden strips are placed edge-to-edge and are enclosed between hardwood veneer sheets which are glued together under high pressure. The wooden strips in the core run lengthways in order to achieve the maximum strength. They are most preferred choice when lengthy pieces of wood are required for furniture, as they do not tend to bend or sag in the middle. Thus for long bookshelves and benches blockboards are preferred over plywood, as they are stiffer.