In an industrial context, the term "brownfield" refers to a site that has already been used or built on and is to be prepared for a new use or development. These may be factories or former industrial or commercial areas, for example, which present infrastructural challenges.
The revitalization of brownfield factories or sites opens up opportunities to use existing resources and avoid environmental pollution instead of accessing untouched areas. In contrast to the term "brownfield", these are referred to as "greenfield".