What Are Hexadecimal Numbers?
The hexadecimal numerical system (often abbreviated as hex) is a positional numerical system based on 16, that is, using 16 symbols instead of 10 of the traditional decimal numerical system. For the hexadecimal, symbols 0 to 9 are generally used for the first ten digits, and then the letters A to F for the next six digits, for a total of 16 symbols.
The hexadecimal system is widely used in computer science, due to its direct relationship between a hexadecimal number and four binary digits. It is often used as an intermediary, or as a separate numerical system. For example, a byte can be expressed with exactly two hexadecimal digits (instead of three decimals). It is interesting, in fact, to notice that each hexadecimal number corresponds to a nibble, that is, to a four-digit binary number.
The word 'hexadecimal' is peculiar, because the prefix 'hexa' is derived from the Greek(where it means six), and decimal comes from the Latin word for ten.
The hexadecimal system, like any positional numbering system, can also represent fractions, like comma numbers: these representations can be limited or unlimited periodic, analogous to the decimal case.