CompTIA IT Fundamentals (FC0-U61) Practice Exam 2025 - Free IT Fundamentals Practice Questions and Study Guide

The numbering system that utilizes the digits 0-9 and the letters A-F is known as the hexadecimal numbering system. This system is base 16, which means it encompasses 16 distinct symbols to represent values. The symbols include the ten decimal digits (0 through 9) and the six additional characters (A, B, C, D, E, F) that represent the decimal values 10 through 15, respectively.

Hexadecimal is commonly used in computing and digital electronics because it can compactly represent binary numbers. For instance, one hexadecimal digit corresponds to four binary digits (bits), making it easier for programmers and engineers to work with large binary numbers by representing them in a more manageable form.

In contrast, binary numbering uses only two symbols (0 and 1) for its base-2 system, decimal uses ten symbols (0 through 9) for its base-10 system, and octal employs eight symbols (0 through 7) for its base-8 system. Hence, the presence of both numeric characters and alphabetical symbols distinctly identifies hexadecimal numbering.