information romeo... information sierra... information tango etc etc
As in "R", "S", "T"...
It's called the phonetic alphabet. Since single letters might be easily confused, especially over the radio, they are spoken as whole words. The same principle is used to identify aircraft. Number "N123AB" is spoken as "November one two three Alpha Bravo".
If you're unfamiliar with it, google "phonetic alaphabet", and you'll come across the complete list easily enough.
Also, police use a similar alphabet, but not all the words are the same. (Anybody besides me old enough to remember Adam-12? They always read a license number that began Nora, Ocean, Ida...)