U.S. Geological Survey is the nations largest water, earth, and biological science and civilian mapping agency. It collects, monitors, analyzes, and provides scientific understanding of natural resource conditions, issues, and problems. The United States Geological Survey (USGS, formerly simply Geological Survey) is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization has four major science disciplines, concerning biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. Since 2012, the USGS science focus is directed at six topical "Mission Areas", namely 1. Climate and Land Use Change 2. Core Science Systems 3. Ecosystems 4. Energy and Minerals and Environmental Health 5. Natural Hazards 6. Water. USGS researchers publish the results of their science in a variety of ways. Many researchers publish their science in peer-reviewed scientific journals as well as in one of a variety of series that includes series for preliminary results, maps data, and results. These series include: Biological Science Report, Bulletin (B), Circular (CIR/C), Circum-Pacific Map (CP), General Interest Publication (GIP), Geologic Quadrangle (GQ) Map, Oil and Gas Investigations (OC) Chart etc., The United States Geological Survey Library holds copies of current and historical USGS publications, and is the largest earth sciences library in the world. Most publications are available for inter-library loan within the United States. Under the Organic Act, which provided for the formation of the USGS, the library was given extra copies of all USGS publications when published to be used in exchange with other domestic and foreign geological agencies, making the acquisition of the USGS Library collection one of the most cost efficient libraries in the U.S. government.