IP and MAC addressing
3. Internet Protocol or IP
The Internet Protocol was designed to allow devices to exchange data over a network.
The word 'device' is used because they do not have to be computers. For example a factory may have dozens of digital controllers on the assembly line wanting to swap information. They can use IP for this.
The most dominant version of IP is called 'version 4' or IP v4.
Each address is made up of a 32 bit binary number like this:
10111000100011101110111000010001
A bit of maths will tell you that $2^{32}$ devices can be identified with this scheme or roughly four billion devices.