Hexadecimal

Hexadecimal describes is a positional numeral system with a radix, or base, of 16. The digit values are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F. Because each digit has a place value, one can convert a hexadecimal number into a decimal number by translating each digit and then multiplying it by 16. The value of the prior digits are then added to the next. For example, the hexadecimal number A1F is equal to ((("A"x16)+"1")x16)+"F" = (((10x16)+1)x16)+15 = 2,591.

Early computers used a binary coded decimal (BCD) internal notation to store numbers, so that each memory position would hold a separate decimal digit. Later computer designers realized that it would be more efficient to assign computer memory addresses to bytes which could hold any value from 0 to 256. Because 256 was 16*16, computer scientists found it easy to represent the content of each byte as a pair of hexadecimal digits (from 00 to FF). This resulting in the widespread use of hexadecimal notation when dealing with computers.