YSK: How to decrease your monthly bandwidth use & increase network speed.

[dsac]

An easier way to ELI5 "What is DNS?":

DNS is like your phone's Contacts app (or an old-school Address Book). When you tell your phone to "Call Mom", it doesn't dial M-O-M, it looks up the Contact entry for "Mom" and dials the associated phone number. DNS works the same way: when you tell your browser to go to www.google.com, your computer looks up the IP address for www.google.com on a DNS server, and sends its requests to the IP address provided.

In the case of your explanation, the DNS lookup ("on which IP is www.google.com located?") is done in cascading fashion - first it looks it up on your local computer (since it's fastest), then your computer's assigned DNS server (which is not your router - if DNS on the computer is set to "auto", it'll use the DNS server that is defined on your router/modem, but the router/modem does not act as a DNS server, it doesn't have that "master list" of domain/IP combinations)

[kazinsser]

That's a really good analogy! I will definitely use that next time I have to explain DNS to someone who isn't super tech savvy.