Domain Name System (DNS)
What is Domain Name System (DNS)?
The Domain Name System, or DNS, is the distributed system that translates human-readable domain names into IP addresses and other service information so devices can locate and communicate with the correct network resources.
Examples
- When a user types a website name into a browser, DNS helps find the IP address of the web server so the page can load.
- A company uses internal DNS records so employees can reach file servers, printers, and applications by name instead of remembering numeric addresses.
Discover 🔎
Most people use names, not numbers, to reach online services. They remember names like deckr.io or example.com, not long strings of digits. Computers, however, still need IP addresses to know where to send traffic. DNS exists to connect those two worlds.
That makes DNS one of the quiet foundations of modern networking. Websites, email delivery, cloud platforms, software updates, single sign-on portals, and internal business systems all depend on it. If DNS answers are slow, wrong, or unavailable, users may feel as though the whole service is broken even when the actual server is still running.
Summary 📝
DNS is the distributed naming system that helps devices find the correct network destinations behind human-readable names. It works through a hierarchy of resolvers and authoritative servers, uses different record types for different purposes, and relies heavily on caching for speed and efficiency. Because so much communication depends on DNS, it is both a core operational service and an important security focus.
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