What is DNS?
The internet's phone book. Translates zorc.se into an IP address so your browser finds the right server.
DNS stands for Domain Name System and works like the internet's phone book. It translates a name you can easily remember, such as zorc.se, into the numeric address (IP address) that computers actually use to find the right server.
Imagine you want to call a friend but only remember their name, not their phone number. You look the name up in the phone book and get the number. DNS does exactly the same for the web: you type an easy-to-read name, and DNS looks up the complicated numeric address behind the scenes so your browser reaches the right place.
All of this happens in a fraction of a second every time you visit a site, without you noticing. But if DNS is misconfigured, nobody reaches your site or email — much like having the wrong number in the phone book.
Why does DNS matter for your business?
DNS determines whether people can reach your site at all and whether your email gets through. When it is set up correctly, everything works seamlessly; when it is wrong, your whole online operation can become unreachable.
DNS also controls important things behind the scenes, such as where your email should be delivered and how you prove your domain is genuine. Correct DNS settings reduce the risk of your emails landing in spam and protect against someone impersonating you.
DNS in practice
Say you change web host and move your site to a new server. You then point DNS so that zorc.se leads to the new address instead of the old one. For a short period, different visitors may see different versions while the change spreads across the network.
Another common case is email: when you set up business email on your own domain, special DNS records are configured so mail is sent and received correctly, and so recipients trust that it comes from you.
Common questions about DNS
What does DNS mean?
DNS means Domain Name System and works like the internet's phone book. It translates a domain name such as zorc.se into the IP address computers need to find the right server.
Why does my site not work after a DNS change?
A DNS change can take anywhere from a few minutes to a full day to propagate across the internet. During that time, some visitors may see the new version and others the old one, until everything has updated.
What does DNS have to do with email?
Special DNS records control where your email is delivered and prove that your messages are genuine. Correct settings reduce the risk of mail ending up in spam or someone forging your sender address.
Related terms
Serverless
There are still servers — you just do not need to worry about them. Someone else has the headache. You have the app.
API
Application Programming Interface. Think of a waiter who takes your order (request) and brings the food (data) from the kitchen (server).
Cache
Stored data that loads instantly instead of being fetched again. Often the reason your site feels fast — or why changes do not show up.
CDN
Content Delivery Network — copies of your site spread around the world so it loads quickly wherever your visitors are.
Cloud
Someone else's computers. Servers in massive data centres you rent instead of own — AWS, Google Cloud, Azure.
Database
Where all your data lives — users, orders, everything. Lose the database and you lose everything, which is why we back it up.