What DNS is
The Domain Name System (DNS) is the internet's directory service. People remember names like whatip.xyz, but machines route traffic using IP addresses. DNS bridges that gap by translating names into addresses so a browser knows where to send its request.
How a lookup works
When you type a domain, your device asks a resolver, which works through a chain of servers:
- A root server points to the right top-level domain, such as
.xyz. - A TLD server points to the domain's authoritative name servers.
- The authoritative server returns the final answer, often an A or AAAA record.
Resolvers cache answers for a period set by the record's TTL, so repeat lookups are fast and do not hammer the upstream servers.
Why it matters
DNS underpins nearly every online action. If it fails, sites become unreachable even when the servers are healthy, because nothing can resolve the name. DNS also enables email routing through MX records, domain verification, and load distribution across servers. For example, changing an A record lets you move a site to a new host without changing its name. You can trace these answers with the WhatIP dns-lookup tool.