What is a defining feature of the hexadecimal number system?

The defining feature of the hexadecimal number system is that it operates as a base-16 system, utilizing a combination of the digits 0 through 9 and the letters A through F. In this system, the digits 0 to 9 represent the values zero to nine, while the letters A to F represent the values ten to fifteen. This allows hexadecimal to efficiently represent large numbers in a more compact form compared to binary (base-2) or decimal (base-10) systems.

This feature is particularly useful in computing and digital electronics, where binary is the underlying representation. Since each hexadecimal digit corresponds to four binary digits (bits), it simplifies the conversion between binary and human-readable formats. For example, the hexadecimal number '2A3' can be easily translated into binary, making it advantageous in programming and hardware design.

In contrast, the other options describe different number systems or incorrect characteristics that do not apply to hexadecimal. Therefore, the correct understanding of the hexadecimal system emphasizes its base-16 nature, enhanced by its character set of numbers and letters.