Roger, in Military radio procedure means transmission received it is usually followed by the word "out" meaning end of conversation. Standard radio procedure makes it possible for different branches of the military to communicate effectively, clearly and concisely over the radio. A transmission using proper military procedure insures that parties do not talk at the same time. An example: headquarters call sign - Druid, patrol call sign - Druid Oscar ( the headquarters call sign precedes the patrol call sign when conversing with units not assigned to Druid. Oscar represents the letter "O".
The transmission: Druid Oscar this is Druid, over.
Druid Oscar, over (connection established)
Druid: Proceed to meet Druid November at, I Shackel, Alpha, November, Sierra, Foxtrot, Oscar, x-ray copy, over.
Druid this is Oscar I copy meet with November Shackel Alpha, November, Sierra, Foxtrot, Oscar, x-ray wilco over,
This is Druid Roger Out.
Druid this is Druid November Roger your last,Out.
Shackel is a code changed daily where the letter represents a number, in this instance, a map coordinate. A, N, S, F, O, X two letters could equal the same number 9 3 3 4 0 6.