Binary number
From ScienceZero
The binary numeral system is a positional notation with a radix of 2. The symbols used in writing is usually 0 and 1.
Each binary digit has double the value of the preceding one, the first digit has the value 1.
0001 = 1 0010 = 2 0100 = 4 1000 = 8
Summing up the values for the digits that are 1 gives the number in decimal. So for the binary number 0110 we get:
0001 0010 = 2 0100 = 4 1000 -------- 0110 = 6
Since each digit is half the value of the bit to the left and double the value of the bit to the right it is simple to divide or multiply a number by two by just shifting all bits just one position to the right or left. This is often the key to efficient computer programming.