For example here is a simplified DNS zone record for xyz.com.
|Domain Name||IP Address|
As you can see xyz.com is on the number 184.108.40.206
How DNS works:
If you want to visit Google.com you will open a web browser and type google.com into the address bar.
Your computer then uses DNS to pull up the nameservers for google.com. Their nameservers are set to ns1.google.com and ns2.google.com.
Your computer will then ask google nameservers for the A record Address for google.com.
The nameservers will then reply back with the IP address that is set as the A record 220.127.116.11.
your computer will send a request to that IP address along with the page you are requesting.
The server that is hosting google.com will then send your web browser the requested page.