In the early days of networking, if you wanted to send a message from one machine to another, you manually entered the IP address. This quickly became unsustainable as the network grew and heaps of websites were created. Then, in 1983, network engineer Paul Mockapetris introduced the Domain Name System (DNS), which allowed the internet to grow into the massive global network it is today. It’s basically the foundation on which the internet works.
DNS translates a domain name like www.example.com into four sets of numbers that comprise that domain’s IP address. It saves users the hassle of having to memorize seemingly random strings of numbers—the IP address—and it’s why DNS is often called “the phonebook of the internet.”
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