This video is about the base 16 number system, namely hexadecimal, or hex for short. Some of the many applications of hexadecimal are mentioned; applications that rely on a compact way of displaying very large numbers, such as colour codes, memory location addresses, MAC addresses, encryption keys, and more. The video compares counting in hexadecimal with counting in denary and binary. It then shows you how to convert denary numbers two and from hexadecimal using place values that increase in powers of 16. You will also see a method that allows you to convert quickly between hexadecimal and binary, which provides a quick way to get from denary to hexadecimal. There are some examples you can try yourself, along with the solutions.