A way to store numbers, computers read in 1s and 0s (binary). To save space on the screen, hexadecimal is used instead of binary. This also helps with recognizing patterns.

One byte is 2 digits long, the valid digits are

• 0
• 1
• 2
• 3
• 4
• 5
• 6
• 7
• 8
• 9
• A
• B
• C
• D
• E
• F

To convert a hexadecimal number into decimal, take 16 and raise it to it's own place, then do this for each digit, then add them together (or use this)