Note: The increasing use of radio-telephones and the concurrent likelihood of misunderstanding what the other person was trying to yell over poor instruments, especially during combat, led to the common practice of substituting a word for each letter of the alphabet. As usual with much military technology, navies often saw the advantages of this sort of system before their landlubber compatriots.
I've only been able to find the British phonetic alphabets for the Great War. If anyone has a US, French, or German list, I'd appreciate it if you'd pass it on to me.
| Letter | 1904 | 1914 | Royal Navy Great War |
| A | ACK | ACK | APPLES |
| B | BEER | BEER | BUTTER |
| C | C | C | CHARLIE |
| D | D | DON | DUFF |
| E | E | E | EDWARD |
| F | F | F | FREDDY |
| G | G | G | GEORGE |
| H | H | H | HARRY |
| I | I | I | INK |
| J | J | J | JOHNNIE |
| K | K | K | KING |
| L | L | L | LONDON |
| M | EMMA | EMMA | MONKEY |
| N | N | N | NUTS |
| O | O | O | ORANGE |
| P | PIP | PIP | PUDDING |
| Q | Q | Q | QUEENIE |
| R | R | R | ROBERT |
| S | ESSES | ESSES | SUGAR |
| T | TOC | TOC | TOMMY |
| U | U | U | UNCLE |
| V | VIC | VIC | VINEGAR |
| W | W | W | WILLIAM |
| X | X | X | XERXES |
| Y | Y | Y | YELLOW |
| Z | Z* | Z* | ZEBRA |
*pronounced "zed" by British Dominion, "zee" by Yanks.