Recycling is the process of converting waste materials into new materials and objects. It is an alternative to "conventional" waste disposal that can save material and help lower greenhouse gas emissions (compared to plastic production, for example
). Recycling can prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, thereby reducing: energy
usage, air pollution (from incineration), and water pollution (from landfilling).
Recycling is a key component of modern waste reduction and is the third
component of the "Reduce, Reuse , and Recycle" waste hierarchy.
There are some ISO standards related to recycling such as ISO 15270:2008 for plastics waste and ISO 14001: 2004 for environmental
of recycling practice.
Recyclable materials include many kinds of glass , paper , and cardboard
, metal , plastic , tires, textiles, and electronics
. The composting
or other reuse of biodegradable waste —such as food or garden waste —is also considered recycling. Materials to be recycled are either brought to a collection center
or picked up from the curbside, then sorted, cleaned, and reprocessed into new materials destined for manufacturing .
In the strictest sense, recycling of a material would produce a fresh supply of the same material —for example
, used office paper would be converted into new office paper or used polystyrene foam into new polystyrene. However, this is often difficult
or too expensive (compared with producing the same product from raw materials or other sources), so "recycling" of many products or materials involves their reuse in producing different
materials (for example
, paperboard) instead.