Glossary / Web fundamentals

DNS (Domain Name System)

DNS is the internet's directory service: it translates human-readable domain names like vantyrex.com into the numeric IP addresses machines actually connect to. Every website visit starts with a DNS lookup, and answers are cached along the way so repeat lookups are nearly instant. A misconfigured DNS record can make a site unreachable for some visitors while working for others — which is why DNS changes deserve engineering care.