..

Word - Understanding this word

A word in computer science is a very important topic to understand if you want to play with low level concepts, or just try to program in assembly. A word is a pre-defined amount of bytes, we can call this a fixed-sized data unit. This unit means how much the processor can grab in a single operation.

Depending on the architecture of the machine, word sizes can be 8, 16, 32, or 64 bits. We don’t use call define the amount of bits when we talk about a word, but the amount of bytes.

• 8-bit (1 byte)
• 16-bit (2 bytes)
• 32-bit (4 bytes)
• 64-bit (8 bytes)

Memory in a computer is organized in bytes, but CPUs often read and write data in words rather than bytes to improve efficiency. So, the larger the word size, the more memory the system can address. And the larger the word, the more data the processor can handle in one clock cycle, increasing the throughput.

Each CPU has a set of registers, which are fast storage boxes. These registers typically hold one word. The word size defines how much data these registers can store and operate.

How can it affect the upper levels of a machine?

A word determines the size of fundamental data types like int, long, float, etc. , in programming languages. Impacts how software written for one architecture works on another. And, affects how fast the system processes data.

About performance, I have an observation to do, even though larger word sizes generally lead to faster computation as more data is processed per operation, this can come at the cost of greater memory usage. So be aware on what you are moving in the machine.

Thanks, bye!

References:

BARTLETT, Jonathan. STL Programming from the Ground Up. 1. ed. 2004.