The Domain Name System translates human-readable domain names like `google.com` into numerical IP addresses that computers use. Without it, you'd have to memorize strings of numbers to browse the web. It acts as the internet's phonebook, connecting names to their server locations for browsers and email systems to function.

DNS relies on specific record types to manage different tasks. A and AAAA records point a domain to its server's IPv4 and IPv6 addresses. CNAME records create aliases for other domains, while NS records delegate authority to a domain's name servers. MX records direct email, and TXT records hold verification data for security services.

When you visit a site, your browser queries DNS to find the correct IP. It first checks the NS record to identify the authoritative server, then requests the A/AAAA record for the IP address. This entire lookup happens in milliseconds, making the web's addressing system seamless for users. Understanding these components is key for developers managing domains and email.