The zoo is a facility in which animals are housed within enclosures, displayed to the public, and in which they may also breed. The term zoo" is derived from the Greek word "zoion," meaning "animal." The purpose of zoos has changed over time from being places of entertainment to becoming institutions for conservation and education.Today, zoos play an important role in the conservation of endangered species and the education of the public about the importance of animal welfare and biodiversity. Many zoos also conduct important research on animal behavior and husbandry."