The acronym DNS stands for Domain Name System. Its primary function is to translate human-readable domain names (like www.example.com) into numerical IP addresses that computers use to identify each other on the network. DNS acts as the phonebook of the internet, facilitating navigation by ensuring that users can access websites easily and securely. Without DNS, users would have to remember complex IP addresses, complicating internet usage. It plays a crucial role in optimizing the speed and reliability of web communications.