DNS records explained simply

DNS is the phone book of the internet: it translates your domain name into a server address. In practice a handful of record types is all you need.

A and AAAA

These say which server your domain points to. A for the classic addresses, AAAA for the newer ones. This is the record you change when you move hosting.

CNAME

A forward from one name to another. Handy for subdomains that should always follow your main domain.

MX

This says where your mail arrives. It is entirely separate from where your website sits: you can move your site without touching your mail, as long as you leave this record alone.

TXT

Free text, used among other things for SPF, DKIM and DMARC. These records decide whether your email lands in the inbox or in spam.

Propagation

A change is not visible everywhere at once. That depends on the time-to-live you set. Lower that TTL a day before a planned move and you save yourself hours.