The Domain Name System (DNS) is a system that translates human-friendly domain names, like www.example.com, into numerical IP addresses, such as 192.0.2.1. This process allows users to access websites without needing to remember complex strings of numbers. DNS functions like a phone book for the internet, helping browsers locate the correct servers to retrieve web content. When you enter a domain name, your device queries a DNS server, which then provides the corresponding IP address, enabling seamless communication between your device and the desired website.