Is 1 Byte Always Equal to 8 Bits?

Byte Size Variation: When 1 Byte ≠ 8 Bits

In the realm of programming, it's commonly assumed that 1 byte comprises 8 bits, but this isn't universally true. Historical systems and modern specialized architectures challenge this convention.

Historically, systems like the PDP-8 (12-bit byte) and early microcontrollers (4-bit byte) employed non-8-bit byte sizes. However, these systems have largely vanished in favor of the ubiquitous 8-bit byte.

In modern times, certain digital signal processors (DSPs) and embedded systems may deviate from the 8-bit byte convention. These machines often employ a minimum type size of 12, 14, or even 16 bits to accommodate specialized processing needs.

For example, Windows CE (a discontinued mobile operating system) introduced a 16-bit smallest type with Microsoft's compiler. However, instead of treating char as 16 bits, Windows CE opted to omit support for char altogether.

Therefore, while the 8-bit byte remains prevalent in mainstream computing, it's essential to note the existence of systems where 1 byte may have a different size. When working with these architectures, relying on CHAR_BIT as a language-agnostic constant for converting between bits and bytes becomes crucial, ensuring precision and avoiding potential errors.

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