Paper is made from a variety of woods, including hardwoods like birch and aspen, and softwoods like pine and spruce. In southern climates, eucalyptus is often used for paper.
Hardwood pulp is used for writing and printing paper because it produces heavy, smooth paper. Alternatively, softwood pulp produces longer pulp fibers making for a stronger, more durable paper to be used in shipping containers, corrugated boxes and shopping bags.
Paper is often made from a blend of both kinds of fibers, in order to combine the qualities of each type of pulp. Recycled paper is usually a blend of both new and recycled fibers, and is most often used to make newsprint, paperboard and tissue paper.