The function of a Domain Name System (DNS) is to translate human-readable domain names into IP addresses, which computers use to identify each other on the network. This system is essential for internet navigation, allowing users to access websites without remembering complex numerical addresses. The DNS operates with a hierarchical structure, consisting of different servers that respond to queries, efficiently directing traffic to the appropriate servers. A functioning DNS is crucial for the internet's usability and performance, as it underpins most online activities.