DNS

DNS — the Domain Name System — is the internet's address book. It translates human-friendly names like yourcompany.com into the numerical addresses computers use, and it directs different kinds of traffic to the right places: your website to one server, your email to another.

It's useful to think of your DNS as a public ledger. It's a record only you control, published openly for the entire internet to read, where you declare how things connected to your domain should behave — which servers handle your mail, which services are authorized to send on your behalf, and how recipients should treat messages that fail those checks.

Because so much depends on it — your website, your email delivery, your email authentication — DNS is foundational infrastructure. Getting it right and keeping it well-managed underpins much of what follows in any IT setup.