A numeral format consisting only of the numbers 1 and 0; other interpretations include "yes or no", "true or false", "on or off", et cetera. This format is largely used in devices where calculation is a
key component; from a simple calculator to the most powerful supercomputers.
A number in this format is composed of bits, with each successive
bit (from right to left) being twice the value of the
bit "before" it, hence the alternate title of "
base-2 number system". If there are "n" total bits, the value of the first
bit will be 2 ^ (n - 1). This
bit is the largest fraction, always greater than, but not equal to, half of the whole number.
The last
bit in a binary number always represents "
one", and this makes it quite important as well. If this
bit is off, the number will be either even, or, if only
one bit is present, just "zero". Turn this bit on, and the number will become
odd.
Binary can be easily converted to a different format by partitioning the bits symmetrically, again from right to left. If the bits are split into threes, the number can become base-8 or octal, while being split into sets of four can make the number base-16 or hexadecimal. It is also possible to convert to base-10 simply by starting from the right and adding 2 ^ (i - 1) each time
bit "i" is equal to 1, until you reach "n".
My current
age is 10100. No, I'm not ancient, that's just another way of saying I'm 20 years
old. The current year, which is
2020 at the time of this post, is also 11111100100 in binary.