There are two primary DNS host record types, IPv4 and IPv6. IPv4 uses a 32-bit IP address in a format that most of us recognize. For example, 192.0.124.23 is an IPv4 IP address. While IPv6 is the newer protocol intended to replace IPv4 because the world is running out of unique IP addresses because of so many computers, mobile devices, and IoT devices. The IPv6 protocol uses 128-bit IP addresses, meaning there are 340 trillion trillion trillion possible unique IP addresses. An IPv6 address looks like this: 26fb:853b:cf05:cda4:1b9d:8fe7:1cf2:abcf. These DNS host record types store a hostname (domain name) and corresponding IPv4 or IPv6 address.