The Astronomical Almanac contains a wide variety of both technical and general astronomical information. The book is a worldwide resource for fundamental astronomical data. The material appears in sections, each section addressing a specific astronomical category. The book also includes references to the material, explanations, and examples.  The book is joint publication between U.S. Naval Observatory and Her Majesty's Nautical Almanac Office (HMNAO) in the UK. HMNAO maintains the copyright on the material it produces.