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What is DNS? Plain-English explanation
DNS, short for the Domain Name System, is the internet's distributed directory service that translates website names such as info100.cc into the numeric IP addresses that computers actually use to find and connect to each other.
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Definition
DNS, short for the Domain Name System, is the internet's distributed directory service that translates website names such as info100.cc into the numeric IP addresses that computers actually use to find and connect to each other.
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- September 7, 2026
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Plain-English explanation
Computers on the internet reach each other by numeric addresses, not by names. DNS is the phone-book-like service that sits between the two. When you type a website name, a DNS lookup quietly asks a chain of cooperating servers to turn that name into the number the network needs. The whole lookup usually finishes in a fraction of a second, and the answer is often reused from a nearby cache so that repeated visits feel instant. Most people never notice DNS until something goes wrong with it.
Why it matters
Without DNS, you would have to remember and type long numeric addresses instead of names like info100.cc. Almost every page load on the internet starts with at least one DNS lookup, which means DNS problems are one of the most common reasons a website appears to be down. Understanding what DNS does also helps you tell a name problem apart from a connection problem when something fails.
Concrete example
When you open info100.cc in a browser, a DNS lookup first changes that name into an IP address. Only after the address is known does the browser open a connection to the site's server and request the page. If the lookup fails, the browser shows an error such as NXDOMAIN or a DNS probe message, and the site never loads even though the server itself may be completely healthy.
Often confused with
A widespread misunderstanding is that DNS encrypts your browsing or that switching DNS servers makes a website secure. DNS is mainly about finding the right server. Privacy and protection of the connection itself come from HTTPS and TLS, which are separate layers that start working only after the DNS lookup has finished.
Short definition: DNS, short for the Domain Name System, is the internet's distributed directory service that translates website names such as info100.cc into the numeric IP addresses that computers actually use to find and connect to each other.
Plain-English explanation
Computers on the internet reach each other by numeric addresses, not by names. DNS is the phone-book-like service that sits between the two. When you type a website name, a DNS lookup quietly asks a chain of cooperating servers to turn that name into the number the network needs. The whole lookup usually finishes in a fraction of a second, and the answer is often reused from a nearby cache so that repeated visits feel instant. Most people never notice DNS until something goes wrong with it.
Why it matters
Without DNS, you would have to remember and type long numeric addresses instead of names like info100.cc. Almost every page load on the internet starts with at least one DNS lookup, which means DNS problems are one of the most common reasons a website appears to be down. Understanding what DNS does also helps you tell a name problem apart from a connection problem when something fails.
Concrete example
When you open info100.cc in a browser, a DNS lookup first changes that name into an IP address. Only after the address is known does the browser open a connection to the site's server and request the page. If the lookup fails, the browser shows an error such as NXDOMAIN or a DNS probe message, and the site never loads even though the server itself may be completely healthy.
Common confusion
A widespread misunderstanding is that DNS encrypts your browsing or that switching DNS servers makes a website secure. DNS is mainly about finding the right server. Privacy and protection of the connection itself come from HTTPS and TLS, which are separate layers that start working only after the DNS lookup has finished.
Related terms
Domain Name, IP Address, Server, Website Address
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More context
DNS was created in 1983 to replace a single file (HOSTS.TXT) that listed all hostnames. It's now a global, decentralized system managed by ICANN and various registries. DNS also supports security extensions (DNSSEC) to prevent spoofing, though not all domains use it.
Additional background
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