# DNS glossary

Authoritative DNS server
  A DNS server which recursive DNS servers contact in order to resolve a given DNS node

DNS node
  A name which DNS usually converts in to an IP, such as www.yahoo.com. Not all DNS nodes have IPs, however.

DNS record
  A single piece of DNS data, which can either be data for a DNS node, or meta-data which DNS uses.

DNS server
  A program which resolves DNS records

DNS server administrator
  A person who manages DNS; setting up DNS servers, changing DNS records, and what not.

Domain registry
  A domain registry is a company that allows one to have their authoritative DNS servers be contacted by recursive name servers.

Domain suffix
  The part of the domain which is (usually) after the first dot in a DNS node. The domain suffix for www.yahoo.com, for example, is yahoo.com.

Domain zone
  A domain zone is a set of one or more DNS nodes. All names in a given domain zone share the same domain suffix.

IP
  A number which a computer connected to the internet has, similar to a phone number.

Internet service provider
  An internet service provider (or ISP) is a company that offers access to the internet.

Mail Transport Agent
  A computer program which accepts incoming SMTP (email) connections, allowing a server to receive email.

Recursive DNS server
  A recursive DNS server is a DNS server which contacts other DNS servers to resolve a given DNS node.

To resolve
  To convert a DNS node, such as www.yahoo.com, in to an IP, such as 10.17.243.32.

To serve
  The action of an authoritative DNS server making DNS nodes available to recursive DNS servers.

Static IP address
  A static IP address is an IP addresses whose value does not change. Only some internet service providers offer static IP addresses.