Another very useful numbering system used in microcontrollers is the Hexadecimal system. The hexadecimal system has a base number of 16, as opposed to the decimal system’s base of 10, and 2 for binary. The 16 symbols required for each digit consists of the standard 0 to 9, plus the first 6 letters of the alphabet: A, B, C, D, E and F. Each symbol is a type of shorthand for a nibble binary number and this makes it a lot easier when writing down binary numbers, you can instead just write down the hexadecimal value. Below is a table showing the relation between Decimal, Binary and Hexadecimal number systems.
Decimal 
Binary 
Hexadecimal 

Decimal 
Binary 
Hexadecimal 
0 
0000 
0 
8 
1000 
8 

1 
0001 
1 
9 
1001 
9 

2 
0010 
2 
10 
1010 
A 

3 
0011 
3 
11 
1011 
B 

4 
0100 
4 
12 
1100 
C 

5 
0101 
5 
13 
1101 
D 

6 
0110 
6 
14 
1110 
E 

7 
0111 
7 
15 
1111 
F 
Comparison between, Hexadecimal and Binary Values