The Comparison of Electronic Resource's Worksheet of National Library of Iran with UNIMARC & MARC21

The purpose of this research is to consider the extent to which electronic resource’s worksheet of National Library of Iran has used the existing & appropriate fields of UNIMARC & MARC21 for electronic resources and the changes rate of the UNIMARC fields in this worksheet was determined. At first all the essential fields of these two formats for electronic resources were identified and a mapping table of UNIMARC to MARC21 was prepared. The researchers made a unit worksheet by merging of educational CD, CDs without music and electronic resources worksheets of National Library and compared it with the identified fields of UNIMARC & MARC21. fields 481 & 482 introducing new concepts were not found in UNIMARC & MARC21. The concepts of some were changed in order to change "Roman Numbers" to "Sequential Numbers" and from "Copy Date" to "Tale Date". These subfields with their new concepts were not in UNIMARC & MARC21. The findings revealed that UNIMARC and MARC21 didnt have 51 & 84 subfields of electronic resource worksheet respectively, and electronic resources’ worksheet didn’t have 51 fields and 55 subfields of UNIMARC and 109 MARC21 fields.Suggestions: Our suggestion is to apply unused fields & subfields of UNIMARC in electronic resource’s worksheet. For a more complete and compatible worksheet, attention to unused MARC21 fields and subfields and having them confirmed by PUC is necessary.Values: Electronic resources’ worksheet of National Library is based on UNIMARC. Comparing it with UNIMARC showed the unused potentials of UNIMARC. Since MARC21 is more updated, has more metadata schemes and is used by many countries, identifying and using the MARC21 fields for Electronic resources can make a more adapted Iranian worksheet for new demands in this age.