Which of the following is/are true about the Z 39.50?

A. It is an international (ISO 23950) standard

B. The contextual Query Language is not based on Z 39.50 semantics

C. It was originally approved by the National Information Standards Organisation (NISO) in 1988

D. It is maintained by IFLA

Choose the correct answer from the options given below:

The correct answer is A and C.

Key Points

• Z39.50:
  • Z39.50 is an international standard client-server, application layer communications protocol for searching and retrieving information from a database over a TCP/IP computer network,

  • It adheres to the ANSI/NISO standard Z39.50 and the ISO standard 23950.

  • It is developed and maintained by the Library of Congress.
  • Work on the Z39.50 protocol began in the 1970s by the National Information Standards Organisation (NISO) and led to successive versions in 1988, 1992, 1995, and 2003.
  • The successors to Z39.50 are the twin protocols SRU/SRW 
  • Z39.50 is commonly used in library settings for tasks like interlibrary catalog searches and loans.
  • It's often integrated into library systems and personal bibliographic reference software. Additionally, it's found in social media platforms like LibraryThing.
  • The Contextual Query Language, formerly known as the Common Query Language, is rooted in Z39.50 semantics.

Additional Information

• ​Z39.71
  • The ANSI/NISO Z39.71 holdings display standard is a combination of two things: the conceptual holdings elements (officially called Data Areas), and nine principles for recording the holdings elements (officially called the Principles).
  • Z39.71 is a standard developed by the National Information Standards Organization (NISO) for searching online library catalogs and retrieving bibliographic records. ​
• Z39.70:
  • Z39.50 is a globally recognized client-server communication protocol, situated at the application layer.
  • t facilitates the search and retrieval of information from databases via TCP/IP computer networks.