Resolution complete. The answer is cached at your OS and recursive resolver. See how the second lookup skips the whole chain.
How DNS works · Key concepts
📖
DNS is the internet's phone book
Humans remember names. Computers route by numbers. DNS maps domain names to IP addresses. Without it, you'd type 93.184.216.34 instead of example.com.
🔄
The recursive resolver does the work
Your device asks one question. The recursive resolver walks the entire hierarchy on your behalf: root → TLD → authoritative. You get one clean answer back.
🌐
The hierarchy: root → TLD → auth
Root servers know TLD servers (.com, .net, .org). TLD servers know which nameservers are authoritative for each domain. Auth nameservers hold the actual records.
⏱
TTL controls how stale data can get
Every record has a TTL in seconds. Short TTLs (60–300s) mean fast propagation when you change IPs. Long TTLs (3600–86400s) mean fewer queries and faster cached lookups.
💾
Caching happens at every layer
Your browser, OS, recursive resolver, and sometimes your router all maintain separate DNS caches. A cold lookup hits the full chain. A warm hit is a local memory read - under 1ms.