The Domain Name System (DNS) is analogousÂ to a very advanced phone book. It allows computers to convert the easy-to-remember domain names (e.g. google.com) into the less than memorable IP addresses (e.g. 220.127.116.11) that computers use to communicate with each other.
When I was at university, one of my classes reviewed many networking principles. One of these was DNS. I distinctly remember being shown a video explaining the basics of a DNS request. Although I can not find the exact video our was shown, the following makes an excellent substitute.
This video explains the basics of a DNS request – the kind of request your computer (or your Internet service provider) sends out to lookup a domain name and retrieve the related IP address(es).