MARC: keystone for library automation

Libraries' most central and costly activity-cataloging material and maintaining the catalogs providing end-user access-had requirements that defied efficient automation until the mid-1960s, when the Library of Congress developed the MARC format for data records. The format became the foundation for automated systems for libraries that took data sharing to new levels and enabled exploitation of future computer developments to create today's online catalog environment. This article describes the complexity of the library application, how the MARC format was innovative, and why it was the foundation of automated systems development in libraries.