NATO phonetic alphabet by those who exchange voice messages by radio or telephone, regardless of language differences or the quality of the communication channel. The 26 code words in the NATO phonetic alphabet are assigned to the 26 letters of the English alphabet in alphabetical order as follows: , Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, , Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu. Strict adherence to the prescribed spelling words is required in order to avoid the problems of confusion that the spelling alphabet is designed to overcome. As noted in a
International Phonetic Alphabet International Phonetic Association" recommended the use of for a velar plosive and for an advanced one for languages where it is preferable to distinguish the two, such as Russian, this practice never caught on. The 1999 "Handbook of the International Phonetic Association", the successor to the "Principles", abandoned the recommendation and acknowledged both shapes as acceptable variants. The International Phonetic Alphabet is occasionally modified by the Association. After each modification, the Association provides an updated simplified presentation of the alphabet in the form of a chart. (See History of the IPA.) Not all aspects of the alphabet can be accommodated