In one sentence: DNS, short for Domain Name System, is the internet's address book: it turns a domain name someone types, like yourcompany.com, into the numeric address of the machine that serves your website, and the same set of records tells the rest of the internet where to deliver your email.
Computers do not find each other by name. They find each other by number. When a customer types your domain into a phone, the phone asks a DNS server one simple question: what is the current address for this name? It gets a number back, connects to that machine, and your homepage loads. The whole exchange takes a fraction of a second and nobody ever sees it happen.
Your domain carries a small set of records that answer those questions. One record says where the website lives. Another says where mail sent to your domain should be delivered. Others prove to mail providers that a message really came from you, or verify to some service that you are the one who controls the domain.
The picture that sticks: your domain is the name on the door, and DNS is the directory that tells everyone which building that door is in. Move to a new building and the name stays the same, but somebody has to go update the directory.
Those records do not have to live where you bought the domain. They can sit with the registrar, with your host, or with a separate service, and plenty of businesses have the domain in one account and the records answering for it in another without ever knowing. Which account actually answers for your domain is the first question anybody will ask you when something needs changing, so it is worth finding out on a calm day rather than a bad one.
DNS is invisible right up until a record is wrong, and then it is the loudest problem you have. Point the website record at the wrong place and the site goes dark. Change a mail record while setting up something unrelated and quote requests stop arriving with no bounce, no error, and no warning. Nothing looks broken from your own desk either, because your phone may still be holding an older answer it cached earlier.
Two habits cover most of that risk. Keep the account holding these records in your own name rather than your web company's, so nothing about your address depends on staying with one vendor. And have somebody watching the records the way they watch the rest of the site, which is the quiet part of ongoing website maintenance that protects your leads and your email at the same time.
One durable fact worth knowing before you touch anything: DNS answers get cached along the way, so a change does not reach every visitor at the same moment. Schedule a move for a slow stretch, not for a Friday afternoon in the middle of your season.
Three things get mixed together constantly. The domain name is what you rent and what customers read. Web hosting is the machine that stores and serves the actual pages. DNS is the wiring between them, and it is the reason you can change hosts without changing your address. An SSL certificate is the fourth piece: it proves the site answering at that address really is yours, so browsers do not put a warning in front of your customer.
No. Hosting is where your pages are stored and served from. DNS is the lookup that tells a browser which host to ask. You can move to an entirely new host and keep the same domain, and the only thing that changes is a record or two.
You should, with your web company added as a user or given access when there is work to do. Records that live only inside a vendor's account are a common reason a business cannot move its site or fix its email quickly when that relationship ends.
Website maintenance · Domain name · Web hosting · SSL certificate · CDN · All glossary terms · Plain-English answers · All services
Free consultation, plain-English advice. If you don't need us, we'll say so.
Book a free consultation → Or call/text directly: (407) 694-2055Tell us a little about the business and we will come back with an honest read: what we would fix first, what it costs, and whether you need us at all. Prefer to see work before you talk numbers? Get a free homepage mockup, built for your business, yours to keep either way.
Brandon reads every one of these himself. You will hear back shortly with an honest read on what we would do first, what it costs, and whether it is worth it for you.