How DNS Resolves a Domain Name

Every website has a numeric IP address, but people type names like 'example.com'. DNS is the system that turns a name into the matching IP address. A resolver, often run by an internet provider or a public DNS service, does this by asking a chain of servers: first a root server, which points toward a server for the domain's ending (like .com), which in turn points to the authoritative server holding the actual record for that specific domain. Once found, the answer is kept in a cache for a set amount of time, called the TTL, so the same lookup does not need to be repeated on every visit.