Recycling is the process of converting waste materials into new materials and objects. This concept often includes the recovery of energy from waste materials. The recyclability of a material depends on its ability to reacquire the properties it had in its original state. It is an alternative to "conventional" waste disposal that can save material and help lower greenhouse gas emissions. It can also prevent the waste of potentially useful materials and reduce the consumption of fresh raw materials, reducing energy use, air pollution (from incineration) and water pollution (from landfilling).
Recycling is a key component of modern waste reduction and represents the third step in the "Reduce, Reuse, and Recycle" waste hierarchy, contributing to environmental sustainability and resource conservation. It promotes environmental sustainability by removing raw material input and redirecting waste output in the economic system. There are some ISO standards related to recycling, such as ISO 15270:2008 for plastics waste and ISO 14001:2015 for environmental management control of recycling practice.