DNS is the name service provided by the internet for TCP/IP networks.

• DNS are broken into domains, a logical organization that computer exists in a large network.
• The domains exists at different levels & connect in a hierarchy that resembles the root structure of atree.
• Each domain extends from a node above it, begening at the top with the root-level domain.
• Under those are the top-level domain, under those top are the second-level domains, & on down into subdomains.
• DNS namspace identifies the structure of domains that combine to form a complete domain.
• QUIT:- Indicates conversation is over.