I've been reading how memory works from a book. The problem is my weak english so I can't catch the meaning correctly.
The text from the book :
A computer with a 32-bit word has 4 bytes/word, whereas acomputer with a 64-bit word has 8 bytes/word. The significance of aword is that most instructions operate on entire words, for example, adding two wordstogether. Thus a32-bit machine will have 32-bit registers and instructions for manipulating 32-bit words, whereas a 64-bit machine will have 64-bit registers and instructions for moving, adding, subtracting, and otherwise manipulating 64-bit words.