Park ranger
A park ranger, park warden, or forest ranger is a person entrusted with protecting and preserving parklands – national, state, provincial, or local parks. "Parks" may be broadly defined by some systems in this context, and include protected culturally or historically important built environments, and is not limited to the natural environment. Different countries use different names for the position. "Warden" is the favored term in Canada, Ireland, and the United Kingdom. Within the United States, the National Park Service refers to the position as a park ranger. The U.S. Forest Service refers to the position as a forest ranger. Other countries use the term "park warden" or "game warden" to describe this occupation. The profession includes a number of disciplines and specializations, and park rangers are often required to be proficient in more than one.
Park police
Park police are a type of security police who function as a full-service law enforcement agency with responsibilities and jurisdiction in park areas primarily located in cities and other urban areas. In addition to performing the normal crime prevention, investigation, and apprehension functions of an municipal police force, the park police may be responsible for policing other public areas and may also share law enforcement jurisdiction with a force of park rangers tasked with the same law enforcement powers and responsibilities.