The International Civil Aviation Organization (ICAO) assigned codewords acrophonically to the letters of the English alphabet, so that critical combinations of letters and numbers are most likely to be pronounced and understood by those who exchange voice messages by radio or telephone, regardless of language differences or the quality of the communication channel.
A a Alpha
B b Bravo
C c Charlie
D d Delta
E e Echo
F f Foxtrot
G g Golf
H h Hotel
I i India
J j Juliet
K k Kilo
L l Lima
M m Mike
N n November
O o Oscar
P p Papa
Q q Quebec
R r Romeo
S s Sierra
T t Tango
U u Uniform
V v Victor
W w Whisky
X x X-ray
Y y Yankee
Z z Zulu