HomeThe UKMARC Manual
| The British Library adopted MARC 21 as its cataloguing format in June 2004. Since that date, these pages have not been maintained. Information on our current practices can be found on our Bibliographic Standards pages. |
Structure of the UKMARC format
The UKMARC format provides a record structure for the description of bibliographic and other items and identifies and describes the data elements within that record. To date the UKMARC format has been defined for books, serials, cartographic items, music and audio-visual materials, but originally UKMARC was used for the exchange of bibliographic records on magnetic tape and the way in which records are organised reflects this.
Because computers can only store and manipulate numbers, the data content within a UKMARC record, i.e. a traditional catalogue record as defined by AACR2, consists of strings of characters arranged in fields. The UKMARC format uses the Extended ASCII (American Standard Code for Information Interchange) character set to determine the numeric value to be used for each character of data. The data content of these fields, or the subfields within them, may be indicated by either a tag or by its position in the record. The end of each field is indicated by a character usually represented as a # (a special character with no ASCII equivalent).
The UKMARC format uses tags consisting of three numeric characters, e.g. 100, and, wherever possible, parallel meanings have been preserved between tags, e.g. between fields 100 and 700. Tags 950-999 and all tags ending in 9 are reserved for local use. UKMARC specifies no structure or meaning for local fields. Theoretically, all fields except 001 may be repeated, but the nature of the data often precludes repetition, e.g. a bibliographic record may contain only one main title.
There are two types of fields: fixed length fields, in which coded characters in particular character positions give information about the item, e.g. whether the item is a monograph or a serial; and variable-length fields, in which the sense of the data is not dependent on a particular character position, e.g. title.
Fields are arranged in functional blocks, sometimes referred to as areas. These blocks organise the data according to its function in a traditional catalogue record:
| BLOCKS | DEFINITION |
|---|---|
| 001-009 | Control fields |
| 010-099 | Coded and other information |
| 100-244 | Main entry access points |
| 245-299 | Title and title paragraph |
| 300-399 | Physical description |
| 400-499 | Series statements |
| 500-599 | Notes |
| 600-699 | Subject access points |
| 700-799 | Added entry access points |
| 800-899 | Series access points |
| 900-945 | References |
| 946-999 | Local fields |
Fields 001-009 are termed control fields. Unlike bibliographic fields, control fields do not contain either indicators or subfield codes. Control fields contain either a single data element or a series of fixed length data elements identified by their relative character position.
The data content of a field is further defined by the use of the following elements:
Indicators
Each variable length bibliographic data field in UKMARC records is introduced by two indicators, each in the form of a single character in the range 0-9, A-Z (giving a possible total of 35 values). These digits ‘indicate’ the relationship between the field in which they occur and other fields in the record, and about how the data in the field should be manipulated for catalogue production. For example, the 100 tag, followed by indicators .10, i.e. 100.10, shows that the person is entered under the last element of the name. Indicators are independently defined for each field. Parallel meanings are preserved from field to field whenever possible. The value of each indicator is to be interpreted independently of the other.
Subfields
Subfield codes distinguish data elements within a field that require (or might require) separate manipulation. Subfield codes in the UKMARC format consist of an alphabetic lower case character following a $. Subfield codes are defined independently for each field. Parallel meanings are preserved whenever possible. The order of the subfields is specified by content standards such as the cataloguing rules. Theoretically all data elements may be repeated. However, the nature of the data often precludes repetition. Each subfield code has its own punctuation and typographic value, and therefore no punctuation needs to be input at subfield boundaries. Computer programs can convert the subfield codes to punctuation for the production of printed catalogue output and the punctuation used is detailed in Appendix F. The small amount of additional punctuation used, particularly within notes fields, follows AACR2.
Levels
Levels are 1-digit numbers input following the indicators and separated from them by a colon, e.g. 700.10:1, used to show that a work included within a publication has been catalogued as a bibliographic entity in its own right. The effect is to create a sub-record for a work, within the main record which describes the publication as a whole. For example, levels could be used for cataloguing The Raymond Chandler collection (1983), if a separate entry is required for each of the three novels in that collection. Levels in this sense are not used in BNBMARC records (added entries, i.e. fields 700-745, are used instead), although the 248 field is used to create analytical levels where catalogue entries for parts of a larger item are required, e.g. if the novels of Raymond Chandler were issued in a monograph series and a record required for each one
Repeats
UKMARC records may contain two or more fields with the same tag (irrespective of whether the indicator values are the same). The repeat number, introduced by a forward slash, is used to distinguish between them, e.g. 700.20/0, 700.20/1, 700.10/2
For further information please contact:
The British Library
Bibliographic Development
Boston Spa, Wetherby
West Yorkshire
LS23 7BQ
United Kingdom
Tel: + 44 (0) 1937 546548
Fax: + 44 (0) 1937 546586
Email: bd-info@bl.uk