hexadecimal or octal ?

[masiht]

I have a question why do we use different type of number systems like hexadecimal and octal ? why not the same system.

[Bazzy]

Each numeric base has its pros and cons.
Hexadecimal and octal bases are used as 16 and 8 are 2⁴ and 2³.
In computers numbers are stored as bit sequences so with base 2.
Having those bases makes things easier than the decimal base

http://www.cplusplus.com/doc/hex.html

[Duthomhas]

And here we learn something cool about mathematics: it is abstract -- meaning that it is defined in terms of how you think about it.

More concretely, given a problem, you can think of it in a way that is more beneficial to solving the problem than other ways of thinking about it.


Here's a mind-bender for you: There is no such thing as a two (or any other number).

:-]

[anders43]

Because its practical. E.g. we still use the Babylonians sexagesimal to do this day (base 60) for handling time. Octal is practical because when displaying such numbers you only need digits. Checkout wikipedia for more info.