F1 F1 is the equivalent to saying "Roger That."

It originated from the PC game Battlefield 1942. The "F command keys" were used to relay commands critical to synchronous attacking and defending. By pressing F1 on the keyboard in-game it would take you to the next stage where if you pressed F1 again your character would exclaim, "Roger That." If you pressed F2 you would say, "Negative." There are over 20 orders you can say.
"There's a tank camping our main base."
"F1 F1"

Or in the real world.

"Watch out for that car!"
"F1 F1"
by doomtar July 18, 2005
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