Integers are whole numbers and floating point numbers are numbers with decimal points.
Computers use a fixed number of bits to represent integers. The most common bit-lengths for integers are 8-bit, 16-bit, 32-bit and 64-bit. Programmers choose an appropriate number of bits to represent integers in a program. If you use an 8-bit integer variable in a program, the largest value it can take will be 255.
In binary, it can be more difficult to represent numbers that contain a decimal point. It can also be difficult to represent extremely small or large numbers. Pi is a difficult number for computers to represent as it has an infinite number of decimal places.
Every device on the internet has a unique IP address. The version most used in recent years is version four, also known as IPv4, which uses a 32-bit number system. A complete IP address is normally viewed as a number, such as a series of whole numbers - for example 192.168.0.12. Each number can be between 0 and 255, which allows just over 4 billion unique addresses.
IPv6 is now coming into use. IPv6 uses 16 bits for each section of the address, creating a 128-bit address. This allows potentially almost 80 octillion unique IP addresses.