The purpose of a DNS (Domain Name System) in internet browsing is to resolve domain names into IP addresses. When users enter a website URL, the DNS acts as a translator, directing requests to the appropriate server hosting the desired content. This hierarchical system enhances user experience by allowing the use of human-readable addresses instead of numeric IPs. Additionally, DNS caching improves performance by storing recent queries, speeding up the resolution process. A reliable DNS is essential for seamless internet navigation and accessibility of online resources.