Inter-Library Loan (ILL) System of Online Computer Library Centre (OCLC):
The Inter-Library Loan (ILL) system of OCLC is world's largest online computerised ILL system used by over 5,400 libraries worldwide. OCLC, an online library network, was set up in 1969 in the USA to facilitate co-operative computerised cataloguing. Over the years the number of partcipating libraries increased and the size of its online union catalogue (OLUC) grew manifolds. As OLUC database grew, the combination of bibliographic records and library holdings made it a useful resource for interlending purposes as well. OCLC started its online ILL subsystem in January, 1979. At present the libraries using the OCLC ILL sub-system have online access to over 35 million records held in 23,000-libraries in 63 countries worldwide. In the last 17 years OCLC libraries have transacted 67 million loans using the OCLC ILL sub-system. The system handles over 6 million ILL messages every year. The users of the ILL sub-system have access to 3 online files: a) The OCLC database for bibliographic verification b) The ILL transaction file for transmitting and tracking of the requests and loans, and c) Name Address Directory (NAD) for contact and address information for libraries, publishers and document suppliers.