Final answer:
DNS servers are responsible for mapping domain names to IP addresses, which allows users to access websites using easy-to-remember names instead of numerical IP addresses.
Step-by-step explanation:
DNS servers provide the name-to-IP address mapping for registered devices/servers on the internet. When a user types in a web address, such as 'www.example.com', the request is sent to a DNS server, which looks up the domain name and returns the corresponding IP address, enabling the user's device to connect to the web server hosting the website.
Without DNS servers, users would have to remember the IP addresses of all the websites they want to visit, which is impractical due to the sheer number of websites and the complexity of IP addresses.