That's wrong. 8bit (1 byte) give you 2^8=256 "cells" of memory; 16 (2 bytes) 2^16 = 64K; 32 bits (4 bytes) is 4,294,967,296 (4Gb). It has nothing to do with number of bytes in word. What's matter is number of bits, or binary digits. You can say that byte is 2 bits and "word" is 3 bytes. That doesn't change anything, it's just groups of bits that has names.