What does “copy that” mean

Many answers here are wrong. I served in the Canadian Airborne Signals, and the various US services, and I am a pri ate pilot.

Both terms are ONLY used in one way by all NATO and UN forces, and international air communications.

Roger is yes

Copy is NEVER used, except by a pilot, both civilian and military.

It is used when receiving complicated instructions from air control...usually landing instructions.. As death can result if one thing is wrong.

N1757j to Teterboro, permission to land, over

Teterboro to n1757j, when arriving at Soarta VOR, turn 170 . When intercepting Stillwater TURN ,right, airport will be in sight. Report downwind runway 3. Over

N1757k, copy, over

Now, if you say COPY, Air control will say

N1757j, readback, over

If you dont get it exacy right, because you COPIED it, you may be denied landing, or will be paying a visit to traffic control.

The correct term for HEARING, is, believe it or not,

N1757 j to Teterboro, how do you HEAR me, over

Thats it.