Editing MARC standards (section)

===Record structure===

MARC records are typically stored and transmitted as binary files, usually with several MARC records concatenated together into a single file.  MARC uses the [[ISO 2709]] standard to define the structure of each record.  This includes a marker to indicate where each record begins and ends, as well as a set of characters at the beginning of each record that provide a directory for locating the fields and subfields within the record.

In 2002, the Library of Congress developed the MARCXML schema as an alternative record structure, allowing MARC records to be represented in [[XML]]; the fields remain the same, but those fields are expressed in the record in XML [[Markup language|markup]]. Libraries typically expose their records as MARCXML via a [[web service]], often following the [[Search/Retrieve via URL|SRU]] or [[OAI-PMH]] standards.