Variable data fields:

The variable data fields are identified by a field tag in the Directory with the pattern 0XX to 8XX. Two kinds of content designation are always used: two indicator positions stored at the beginning of each field and a two-character subfield code preceding each data element within the field. They may vary in length and may contain any text or other data needed to describe an individual bibliographic item or other type of record.

Variable data fields with tags of the pattern 9XX, AXX to ZXX are locally or system defined and may or may not conform to the above specifications. Some automation systems use tags that cannot be placed in a three character pattern, such as 1000. These systems usually provide a means for removing all non-standard tag numbers when the record is exported to another system.

For information about the variable data fields in a specific MARC format, select:

Variable Data Fields (Authority)

Variable Data Fields (Bibliographic)

Variable Data Fields (Classification)

Variable Data Fields (Community Information)

Variable Data Fields (Holdings)