Encyclopedia / Domain & network
DNS
The internet's phone book. It turns names into IP addresses.
When you visit example.com, a resolver asks the root servers, then the .com servers, then your domain's nameservers. Answers are cached for a time called the TTL, which is why DNS changes can take minutes or hours to spread.
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Where it shows up in a page load
- Step 2: DNS lookup. The browser asks a DNS resolver, the internet's phone book, for example.com. The resolver follows the chain from the root servers to the domain's nameservers and returns an IP address. The answer is cached so the next visit skips this step.
Watch the full request journey →
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How a name like example.com turns into a secure connection to a real machine.