IPv4 and IPv6 are the two versions of the Internet Protocol that give devices their addresses. IPv4 uses 32-bit addresses like 201.54.112.60, which allows just over 4 billion of them. IPv6 uses much longer 128-bit addresses, created because the internet was running out of IPv4 ones. ClickGuard tracks and blocks both.
201.54.112.60
IPv4 is the most widely deployed Internet protocol used to connect devices to the Internet. IPv4 uses a 32-bit address scheme allowing for a total of 2^32 addresses (just over 4 billion addresses).
With the growth of the Internet, it is expected that the number of unused IPv4 addresses will eventually run out because every device -- including computers, smartphones, and game consoles -- that connects to the Internet requires an address.
2001:db8:85a3:0:0:8a2e:370:7334
The Internet Protocol version 6 (IPv6) was designed as an evolutionary upgrade to the Internet Protocol and will, in fact, coexist with the older IPv4 for some time. IPv6 was designed to allow the Internet to grow steadily, both in terms of the number of hosts connected and the total amount of data traffic transmitted.
An IPv4 address is a binary number but can be stored as text for human readers. For example, a 32-bit numeric address (IPv4) is written in decimal as four numbers separated by periods. Each number can be zero to 255. For example, 1.160.10.240 could be an IP address.
IPv6 addresses are 128-bit IP address written in hexadecimal and separated by colons. An example IPv6 address could be written like this: 3ffe:1900:4545:3:200:f8ff:fe21:67cf.

While increasing the pool of addresses is one of the most often-talked-about benefits of IPv6, there are other important technological changes in IPv6 that will improve the IP protocol:
See also: What is an IP address.