What is scientific notation and why do you use it?

Answer 1

Scientific notation is a way to express numbers that are either very small or very large. In traditional notation the first kind would have a lot of 0s between the decimal point and the first significant figure whereas the second kind would have a large number of trailing 0s. The need for scientific notation arose from advances in various branches of science: atomic particles in physics or chemistry, astronomical or cosmological distances, size of single cell animals. Nowadays, even non-scientific values such as population, national debts (of some countries) could usefully utilize scientific notation.

Scientific notation is a way of representing numbers, in the form

a*10b where 1 ≤ |a| < 10 is a decimal number and b is an integer (negative or positive).

a is called the mantissa and b is called the exponent.