Only about thirty non-Navajos could speak Navajo fluently. About four hundred Navajo code talkers could speak it fluently. They wanted the messages to be accurate and able to understand quickly. For example, they named planes after different kinds of birds, and boats after fish.  Some of the letters had more than one word to pronounce it just to confuse others. It probably wasn't even needed, the language wass confusing enough as it was ("The Code Talkers"). To the right: a page of the Navajo dictionary.