1. Domain Name System
DNS - A system for converting host names and domain names into IP addresses on the Internet or on local networks that use the TCP/IP protocol.
For example, be converted into the IP address Without DNS, you would have to type the four numbers and dots into your browser to retrieve the Web site, which of course, you can do. Try finding the IP of a favorite Web site and type in the dotted number instead of the domain name!
DNS server
Yahoo web server
Mapping table inside DNS server ….