4 bytes, 8 bytes or 16 bytes

Question

What is the difference between having 4 bytes or having 8 bytes or having 16 bytes?
And what does it help you with?
For example: float a = 5.32
double a = 5.32
long double = 5.32

Answer 1

This types differ in accuracy
The numerical value of a finite number is
  (−1)s × c × b^q
where b is the base (2 or 10)
https://en.wikipedia.org/wiki/IEEE_floating_point