"Roger" was "phonetic" for "R" (received and understood). In radio communication, a "spelling alphabet" is used to avoid confusion between similarly sounding letters. In the previously used US spelling alphabet, R was Roger, which in radio voice procedure means "Received". While in the current spelling alphabet (NATO), R is now Romeo, Roger has remained the response meaning "received" in radio voice procedure. In the US military, it is common to reply to another's assertion with "Roger that", meaning: "I agree". Major David Null, Auxiliary USAF, Claremont, CA USA

The origin of this phrase, which means "Yes, O.K., I understand you" dates back to the earliest days of wireless communication, when the Morse code letter R (dit-dah-dit) was used to indicate "O.K.--understood." As communications advanced to include voice capabilities, the military alpha code (Able, Baker, Charlie, etc.) was used as a logical extension of such single character responses. R=Roger=understood. Of course, you always hear "Roger, Wilco, Over and Out" in terse military dramas. The additional verbiage means (Wilco) "Will Comply", (Over) "Message Complete--Reply Expected", and (Out) "Message Complete--No Reply Expected".

( or "I have heard what you said" )

roger means yes, roger that means "yes to what you said"