Plywood consists of fine sheets of wood, or veneers bonded with glue. Plywood is a versatile product that can combine attractive surface appearance with superior performance under hazardous conditions while retaining comparatively high strength-to-weight ratios. It is available in a range of wood species, including hardwood and softwood species and combinations of the two, and a range of resin types for interior, high humidity and exterior conditions. Plywood was the first type of board developed to provide panels with dimensional stability and good strength both along and across the panel.