The seven research facilities in the United States are all at universities (see below). These research facilities have been deemed "body farms" due to the nature of the decomposition research they perform. Numerous purposes exist for these research facilities, yet their main purpose is to study and form an understanding of the decompositional changes that occur with the human body. This research is then used for medical, legal and educational purposes. Following the outdoor research, skeletal remains are cleaned and curated in permanent known skeletal collections open for research. Such collections are critical for testing and developing new identification methods.