What system resolves a host name to an IP address?

The Domain Name System (DNS) is the system responsible for resolving host names into corresponding IP addresses. When a user types a domain name (like www.example.com) into a web browser, the browser queries the DNS servers to find the associated IP address that corresponds to that domain name. This process is essential for the functioning of the internet, as it allows users to connect to websites easily without needing to remember numerical IP addresses.

DNS operates by using a hierarchical system of servers that can answer queries about domain names, making it a crucial component in network communication. The conversion of human-readable domain names into machine-readable IP addresses is what enables users to navigate the internet seamlessly. Other concepts like URLs (which are formatted addresses including the domain), FTP (a protocol for transferring files), and HTTP (the protocol for transmitting web pages) do not perform the function of name resolution as DNS does.