Build Basics / Standard term
Domain Name System (DNS)
The Domain Name System (DNS) is the internet's address book that translates a domain name people can read, like example.com, into the numeric address a browser needs to find the server that answers for it.
The Domain Name System (DNS) is the internet's address book that translates a domain name people can read, like example.com, into the numeric address a browser needs to find the server that answers for it. People remember words; computers route to numbers, so a lookup step bridges the two. Say you deploy a to-do app and point todoapp.example.com at it. When a visitor opens that address, the browser asks DNS which numeric address it maps to, DNS returns the address of your host, and the browser connects there to load the app. You manage this by editing DNS records at whoever holds your domain, telling them which host the name should point to.
Builder example
When you connect a custom domain to a deployed project, you are setting DNS records that point your name at your host. A wrong or missing record means visitors get an error or land on the wrong server, even though the app itself runs fine. Changes also take time to spread across the internet, so a domain can look broken for minutes or hours after you set it correctly. Tell your AI assistant which host you deployed to and ask it which DNS records to add, then confirm the values before saving.
Common confusion: A domain name is the readable address you register, such as example.com. DNS is the lookup system that maps that name to the numeric address of a server. Buying a domain does not connect it to anything until you set DNS records that point it at your host.