The name is Marx. It means MAchine-Readable Cataloging format standard (English: MARC), which is a communication format standard for book management and is used to exchange catalog information between libraries or publishers. MARC standard follows the catalog format developed by the Library of Congress in the 1970s. Although it is a standard, in fact, MARC is a large collection of format standards of machine-readable cataloging in various countries, and each country still has its own format standards.