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.