In order to understand what the DNS is and how it works, you need to have a basic understanding of IP addresses and domain names. An IP address, or Internet Protocol address, is a complex string of numbers that acts as a BINARY identifier for devices across the Internet. In short, an IP address is the address that computers, servers and other devices use to identify one another online. The vast majority of IP addresses are arranged into four sets of digits - i.e., 12.34.56.78.