Domain Name System (DNS) is a distributed Internet directory service, used primarily to translate between domain names and IP addresses, and to control Internet email delivery.

• DNS Resources Directory
• Reflections on the DNS, RFC 1591, and Categories of Domains - (IETF RFC 3071) primarily for historical context and comparative purposes, essentially to document some thoughts about how 1591 might have been interpreted and adjusted by the Internet Assigned Numbers Authority (IANA) and ICANN to better reflect today's world while retaining characteristics and policies that have proven to be effective in supporting Internet growth and stability, John C. Klensin, February 2001
• Role of the Domain Name System (DNS) - (IETF RFC 3467) reviews the original function and purpose of DNS, contrasts that history with some of the purposes for which the DNS has recently been applied and some of the newer demands being placed upon it or suggested for it, and outlines a framework for an alternative to placing these additional stresses on the DNS, John C. Klensin, February 2003