While trips to the library are needed for research and reference, some basic reference sources are worth purchasing since they are used so often. This is one such reference. Updated yearly, it contains information about the state of the world that is invaluable in writing reports, doing research, or just for browsing. Among the wealth of topics presented are economics, crime, health, science and technology, consumer information, government, U.S. facts and history, U.S. city populations, world history and culture, sports highlights and much more.