A "Greenfield" refers to undeveloped land that has not been previously built upon. This type of land is often found in rural or suburban areas and is typically used for agriculture, recreation, or potential future development. Greenfields are important for urban planning as they provide opportunities for new construction projects, such as residential neighborhoods or commercial spaces. In contrast to Brownfield sites, which are previously developed lands that may be contaminated, Greenfields are generally free from such issues. Developing Greenfield sites can lead to economic growth, but it also raises concerns about environmental impact and the loss of natural habitats.