Question

Why is scientific notation useful?

Answer 1

It condenses very long strings of numbers while retaining the general accuracy of the figure.

Answer 2

Scientific notation comes in handy because it lets us take very big or very small numbers, get rid of all the zeroes,  and write them in a very compact and very simple way that's much easier to use. Also, big numbers aren't just a pain to deal with because of all the digits but they're also hard to quickly evaluate and compare with other numbers.