MatSciNet is a web version of the Mathematical Reviews database from the American Mathematical Society AMS. It contains over 2 million reviews, abstracts and bibliographic data on mathematical literature from around the world. The bibliographic data of retrodigitized articles date back to 1864. The database adds up to 80,000 new items per year, most of which are classified according to the Mathematics Subject Classification (MSC). Together with Zentralblatt MATH, it is the world's leading reference source in mathematics.