What is DNS and how does it work?

Answer

The Domain Name System (DNS) translates human-readable names like example.com into the IP addresses machines use to route traffic. A resolver queries a hierarchy of servers, from root to top-level domain to the domain's authoritative name server, caching answers along the way based on each record's time-to-live (TTL). Common record types include A and AAAA for addresses, CNAME for aliases, MX for mail, and TXT for verification and policy data. DNS changes propagate gradually because caches honor the TTL, which is why updates are not always instant.