Why are 8 and 256 such important numbers in computer sciences?

Viewed 9883

I don't know very well about RAM and HDD architecture, or how electronics deals with chunks of memory, but this always triggered my curiosity: Why did we choose to stop at 8 bits for the smallest element in a computer value ?

My question may look very dumb, because the answer are obvious, but I'm not very sure...

Is it because 2^3 allows it to fit perfectly when addressing memory ? Are electronics especially designed to store chunk of 8 bits ? If yes, why not use wider words ? It is because it divides 32, 64 and 128, so that processor words can be be given several of those words ? Is it just convenient to have 256 value for such a tiny space ?

What do you think ?

My question is a little too metaphysical, but I want to make sure it's just an historical reason and not a technological or mathematical reason.

For the anecdote, I was also thinking about the ASCII standard, in which most of the first characters are useless with stuff like UTF-8, I'm also trying to think about some tinier and faster character encoding...

10 Answers
Related