What Do You Mean By The Word Length Of The Microprocessor?

Microprocessors have internal data pathways and internal registers with a fixed number of bits.  An 32 bit processor will process 32 bit words, a 64 bit processor will process 64 bit words.  The internal registers are sized to accommodate the word length with a single transfer.  Generally, the more bits a processor can handle, the faster it can run.  Smaller microprocessors might only process only 8 bits or less.    

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