Binary code.

Examples of binary.
For 94

128 . 64 . 32 . 16 . 8 . 4 . 2 . 1
  0      1     0     1    1   1   1   0


 For the Binary Number 2.5

8 . 4 . 2 . 1 . 1/2 . 1/4 . 1/8
0   0   1   0     1      0      0

0010100 - This Byte is called the mantissa and shows the number with the decimal placed moved to then end.

0000001 - This Byte is called the exponent and shows how many places the decimal place has been moved.

8 bits is usually called a "byte",
and a  "nybble" is 4 bits;