#### What is Hexadecimal Code (Hex Code) ?

Hexadecimal numerals are used very oftem in computing world as the representation of binary data, as they provide a more human-friendly representation of binary-coded values. Hexadecimal consists of a symbol set made up of `0 - 9`, `A - F`. If you are proficient in using computer or already using it for a long time, you may notice the code or text like `0xBEEF9992`. Those text are hexadecimals.

#### How do I know that a text is a hexadecimal code ?

The rule of thumb of indentifying hexadecimals code is by looking at whether the code is in pair (even number of length) and the character which made text.

If the character is consist of `0 - 9` and `A - F`, and it is in pair (even number length) such as `0xBABEFACE88`, then it is can be considered in hexadecimal notation.

Note : the length of hexadecimal number can be odd number, but it is very uncommon. On most computers/ systems, hexadecimal code is padded by zero (`0`).

Hexadecimal code also can be seen in other form such as:

• `0xBEEFBA22`
• `0xBE 0xEF 0xBA 0x22`
• `\xBE \xEF \xBA \x22`
• `BEEFBA22`

#### Why hexadecimals consisted of 16 chars ?

Well, if you seeing from the perspective of the creator, it is a cool thing to represent 256 possible characters or 1 byte. For example, `0x99` can used to represent decimal number of `153`. Imagine you can use `0xFFFFFF` to represent decimal number of `16777215`.

So, the following word :

``````Roger That!
``````

Represented in Hexadecimal (every line is the same):

``````52 6f 67 65 72 20 54 68 61 74 21 (" " prefix)

0x52 0x6f 0x67 0x65 0x72 0x20 0x54 0x68 0x61 0x74 0x21 (" 0x" prefix)
``````