What numeral system uses base-16 and includes digits 0-9 and letters A-F?

The numeral system that uses base-16 is known as hexadecimal. In this system, numbers are represented using sixteen unique symbols: the digits 0 through 9 represent values zero to nine, while the letters A through F represent values ten to fifteen. This allows for a more compact representation of values compared to decimal (base-10) or binary (base-2).

Hexadecimal is widely used in computing and digital electronics because it can represent large binary numbers in a more readable and manageable form. Each hexadecimal digit corresponds to a group of four binary digits (bits), making it particularly useful in contexts like memory addressing and color representation in graphics.

Other numeral systems mentioned do not fit this description; binary uses base-2, featuring only two symbols (0 and 1), decimal operates on base-10 with digits ranging from 0 to 9, and octal employs base-8 with digits from 0 to 7. Therefore, hexadecimal stands out as the correct answer due to its unique characteristics and applications in computing.