IP Addresses and DNS
Published
If a domain is the name, an IP address is the actual location.
An IP address is basically a number that identifies a server on a network. Websites and services need IPs so devices know where to connect.
DNS (Domain Name System) is the phonebook of the internet. It translates names like metrolux.net into IP addresses, so your browser knows where to go.
Why DNS matters so much: One small wrong record can take your website offline, or break your business email, even if the server is working fine.
Most common DNS records:
A record: points a domain to an IP address (usually used for websites).
CNAME: points a subdomain to another domain (common for "www" or service integrations).
MX: tells the internet where your email is hosted (if MX is wrong, your email will not arrive).
TXT: used for verification and email security records like SPF, DKIM and DMARC.
DNS caching: DNS changes are not always instant. Your device and your internet provider cache results, so sometimes things look "fixed" for you but broken for someone else.
Bottom line
If you understand IP + DNS, you understand why hosting, email, and most "my site is down" problems happen.