Z39.50

Z39.50 is a protocol for searching and retrieving information from remote repositories of content such as databases. Z39.50 is popular in lending libraries and is widely used for inter-library loans. The standard pre-dates web technology by a number of years, however, a number of initiatives such as SRU (Structured Retrieval via URL) have developed gateways to allow searches from intranets or websites to be interpreted by Z39.50 systems.