Lumber in USA and timber in Australian English, British English, and New Zealand English is wood that has been processed into beams and planks, a stage in the process of wood production. Lumber may be supplied either rough-sawn, or surfaced on one or more of its faces. Besides pulpwood, rough lumber is the raw material for furniture-making and other items requiring additional cutting and shaping. It is available in many species, usually hardwoods; but it is also readily available in softwoods, such as white pine and red pine, because of their low cost. Finished lumber is supplied in standard sizes, mostly for the construction industry—primarily softwood, from coniferous species, including pine, fir and spruce (collectively spruce-pine-fir), cedar, and hemlock, but also some hardwood, for high-grade flooring.
Lumber is mainly used for structural purposes but has many other uses as well. It is classified more commonly as a softwood than as a hardwood, because 80% of lumber comes from softwood. Individual pieces of lumber exhibit a wide range in quality and appearance with respect to knots, slope of grain, shakes and other natural characteristics. Therefore, they vary considerably in strength, utility and value.