A radio alphabet is a code used in radiotelephony, which consists of representing each letter of the alphabet by a whole word, chosen acrophonically (with the letter represented as its initial). Thus, when a word is spelled, each of its letters is replaced by the corresponding word, so that there is no ambiguity between similar sounds (such as "m" and "n", "p" and "b"). Such ambiguities are likely to occur because of the noise and interferences that radio transmissions are frequently subjected to, and also because the recipient does not see the speaker and therefore does not have a visual indication to help him lift any ambiguity.