how DNS happening

first let see as flow: user----> DNS query initialization----> sub resolver [local machine] example: www.wikipedia.org . here last [.] represent root org represents TLD [Top level domain] Wikipedia represents SLD [secondary level domain] www represents Zone file root [name server] / | \ / | \ / | \ .org .com .in [Name server] / / / Wikipedia [name server] / / / www ------> IP zone file : A -----> IPV4 AAAA----> IPV6 mx-------> mail When your browser needs to resolve a domain (like www.wikipedia.org. ), it doesn’t directly go to root servers first. It usually goes to a DNS resolver provided by your ISP (Internet Service Provider). Here’s the real-world flow: You Type a Website www.wikipedia.org . Browser Checks Cache If not found → continue Request Goes to ISP DNS Resolver Your device sends the request to: Your ISP’s DNS server Example: Airtel DNS Jio DNS This server is called a recursive resolver ISP Resolver Checks Cache If it already knows → returns IP immediately If not → it starts