Paper is a thin material mainly used for writing upon, printing upon or for packaging. It is produced by pressing together moist fibers, typically cellulose pulp derived from wood, rags or grasses, and drying them into flexible sheets.
Paper is a versatile material with many uses. Whilst the most common is for writing and printing upon, it is also widely used as a packaging material, in many cleaning products, in a number of industrial and construction processes, and occasionally as a food ingredient, particularly in Asian cultures.
Paper recycling is the process of recovering waste paper and remaking it into new paper products. There are three categories of paper that can be used as feedstock for making recycled paper: mill broke, pre-consumer waste, and post-consumer waste. Mill broke is paper trimmings and other paper scrap from the manufacture of paper, and is recycled internally in paper mill.
Pre-consumer waste is material that was discarded before it was ready for consumer use. Post-consumer waste is material discarded after consumer use such as old magazines, old newspapers, office waste, old telephone directories, and residential mixed paper. Paper suitable for recycling is called "scrap paper".
Industrialized paper making has an effect on the environment both upstream (where raw materials are acquired and processed) and downstream (waste-disposal impacts). Recycling paper reduces this impact.
Today, 90% of paper pulp is made of wood. Paper production accounts for about 35% of felled trees, and represents 1.2% of the world's total economic output. Recycling of saves about 1 ton of wood while recycling 1 ton (1.1 short tons) of printing or copier paper saves slightly more than 2 tons of wood. This is because Kraft Pulping requires twice as much wood since it removes lignin to produce higher quality fibers than mechanical pulping processes.
Relating tons of paper recycled to the number of trees not cut is meaningless, since tree size varies tremendously and is the major factor in how much paper can be made from how many trees. Trees raised specifically for pulp production account for 16% of world pulp production, old growth forests 9% and second- and third- and more generation forests account for the balance. Most pulp mill operators practice reforestation to ensure a continuing supply of trees. The Forest Stewardship Council (FSC) certifies paper made from trees harvested according to guidelines meant to ensure good forestry practices. It has been estimated that recycling half the world’s paper would avoid the harvesting of 20 million acres (80,000 km²) of forestland.