<p>A real number is represented as a factor, called the mantissa, multiplied by a power (the exponent) of a base.
Different bases yield different approximations to real numbers, and conversion between them is limited in accuracy.
Four floating-point types are defined in 'IEEE-754 Standard for Binary Floating-Point'.
These types are 'single', 'extended single', 'double', and 'extended double'.
</p>