Explanation

People often wonder what is the differences in bytes (1, 2, and 4). A really simple answer arises. Each byte can hold a different value size:

For example:
Byte Size 1: Maximum of 256 .. 00 to FF
Byte Size 2: Maximum of 65535 .. 00 00 to FF FF
Byte Size 4: Maximum of 4294967295 .. 00 00 00 00 to FF FF FF FF

What is HEX? (binary, decimal, etc)
Hex is a number system based on base 16. Values in memory are represented as hex because the hex numbers are smaller and easier to work with than decimal numbers. Hex uses the numbers 0 - 9 and the letters A - F.

Binary is a base 2 number system. 1001110011100111 is a binary number. You will most likely not have to use this in game hacking.

Decimal is the number system you are probably most familiar with. It is the standard number system and uses a base 10 format. 1, 2, 3, 4, 5, 6, 7..etc

Octal is a base 8 number system.
For Example:
Say you are using a value of 512, 512 cannot be set in byte size 1. Byte size 1 only is capable of holding a max value of 256. Byte size 2 however can hold a max of 65535, so it is capable of holding the value 512. The byte representation of 512 would be:

Anyways, Each numerical value is stored in hex decimal notation which is represented as a byte.