DNS
The phone book of the internet that connects domains to servers.
What is DNS?
DNS (Domain Name System) translates your domain name into an IP address — the actual location of your server. When you "point your domain to Vercel," you're updating DNS records. Changes take minutes to hours to spread globally.
DNS feels complicated, but in practice you're just copying a value from your hosting platform and pasting it into your domain registrar. That's it.
In Vibe Coding
When you "connect a custom domain" in Vercel or Railway, they give you DNS records to add at your domain registrar (Cloudflare, Namecheap, GoDaddy). It usually takes 15 minutes to an hour for changes to take effect.
Example
For example: You buy myapp.com and want it to point to your Vercel site. Vercel tells you: add a CNAME record pointing to cname.vercel-dns.com. You add it at your registrar, wait 30 minutes, and your domain works.