Digital number systems — terminology check. What is a single hexadecimal digit (one 4-bit value) commonly called in digital electronics?

Introduction / Context:
A core idea in digital systems is that 4 bits conveniently map to one hexadecimal digit. Knowing the standard names for common bit-widths makes documentation, debugging, and memory/encoding discussions precise and fast.

Given Data / Assumptions:

• One hexadecimal digit ranges from 0 to F (0–15 in decimal).
• A hexadecimal digit corresponds to exactly 4 binary bits.
• Standard computer-architecture terminology is used (bit, nibble, byte, word).

Concept / Approach:
Each hex digit expands to a 4-bit pattern (0000 through 1111). The well-accepted term for a 4-bit quantity is “nibble” (also spelled “nybble”). Eight bits form a “byte,” and a “word” is an architecture-dependent wider unit (often 16, 32, or 64 bits).

Step-by-Step Solution:

Verification / Alternative check:
Hex is popular because 4 bits align perfectly with one digit, letting engineers compress long binary strings. For example, 0xAB maps to 1010 1011; each 4-bit group (1010 and 1011) is one “nibble.” Documentation and instruction sets frequently refer to high nibble (upper 4 bits) and low nibble (lower 4 bits) of a byte.

Why Other Options Are Wrong:

• Byte: 8 bits, not 4.
• Grouping: a vague term, not a standard size.
• Instruction: an operation encoding; width varies.
• Word: platform-dependent width, larger than a nibble.

Common Pitfalls:

• Confusing nibble with byte due to casual usage.
• Assuming “word” is universally 16 bits; it varies by CPU.

Final Answer:
nibble