The variable-sized word made more sense when writing code to work acoss machines with 16-bit and 18-bit words or 32-bit and 36-bit words. This is also why you

The variable-sized word made more sense when writing code to work acoss machines with 16-bit and 18-bit words or 32-bit and 36-bit words. This is also why you get C99's uint_least32_t and friends, so you're not accidentally forcing a 36-bit machine to have 32-bit overflow behavior everywhere. Before the mid-late 1990s, programmers rarely needed to worry about the difference in size between 32 and 36 bit words.