Why do we need octal


For computer chips the only important thing. Either you have a signal (1) or not (0). But to write a program in binary code is not easy. On paper it's very long combination of zeroes and ones. Man they are hard to read.

The use of the usual decimal system in the computer documentation and the programming is very inconvenient. Conversion from binary to decimal and back is very time - consuming process.
The origin of the octal system, like decimal, are associated with counting on fingers. But it's not the fingers, and the spaces between them. Them as time eight.


The solution was the octal numeral system. At least at the dawn of computer technology. When the bit width of the processor was small. Octal system allowed us to easily translate a binary number to octal and Vice versa.
Octal number system - number system with base 8. To represent numbers uses digits from 0 to 7.


Conversion


In order to convert an octal number to binary, replace each digit of octal numbers to three of the binary digits. It is only important to remember which combination corresponds to binary digits of the number. They are quite a bit. A total of eight!
In all number systems other than decimal, characters are read one at a time. For example, in the octal system, the number 610 is pronounced "six, one, zero".


If you are familiar with binary number system, you can not remember the line numbers of some others.

The binary system is no different from any other positioning system. Each digit in the number has a limit. Once the limit is reached, the current category is reset, and before him appears a new. Only one comment. This limit is very small and equal to one!

It's very simple! Zero will be represented as a group of three zeros 000, 1 will result in the sequence 001, 2 will turn to 010, etc.

As an example, try converting an octal number to binary 361.
Response — 011 110 001. Or, if we discard the insignificant zero, then 11110001.

The translation from binary to octal similar to that described above. Just start splitting at three to the end of the number.