Definition and scope:

The variable data fields include fields 01X-9XX.  They are grouped into blocks according to the first character of the tag, which identifies the function of the data within the record.  The type of information in the field is identified by the remainder of the tag.  Each field is identified by a field tag in the Directory.  Within variable data fields, two kinds of content designation are used:  two indicator positions, stored at the beginning of each field, and a two-character subfield code preceding each data element within the field.

The following are General Information sections for groups of fields with similar characteristics.:

Names and Terms:  Indicators, subfield codes, and input conventions for all the fields which include headings follow similar patterns.  For detailed information, select:  Names and Terms:  X00-X85 Fields.

Tracings and References:  Describes tracing fields, reference fields, simple and complex cross references including examples, input conventions, etc.  For detailed information, select:  Tracings and References - General Information.

Heading Linking Entries:  Includes special indicator and subfields used with 7XX fields, input conventions, history, etc.  For detailed information, select:  7XX Heading Linking Entries - General Information.

For information on a specific variable data field, select a topic:

(Shortcut:  For information on a particular field, use the Tag Lists to search by tag, subject area, or alphabetically.)

Tag range:

Field description:


Numbers and Codes

1XX, 3XX:

Headings ( established and unestablished)

260, 360:

Complex Subject References


See From Tracings


See Also From Tracings


Series Treatment


Complex Name References




Heading Linking Entries


Other Variable Fields


Local Implementation

See also:

Variable Control Fields  (00X)

MARC 21 Format for Authority Data:  Contents