Welcome to the
Not-so-secret

Secret Page of Five by Five

five by five: still friends or allies after a misunderstanding or a bout of personal friction; cool

Five by five is also an expression used in aviation (and maybe other) radio communication to indicate the quality and loudness of received voice transmissions. Rated one to five indicates - first figure - clearness and - second - loudness. Five by five means that a transmission is received clear and loud (as usually stated loud and clear). One by one, on the other hand, means it can hardly be heard and is not understandable. If you have a loud but distorted transmission, you may hear two by five, and a weak but clearly understandable one may be called five by three...

...You get the idea.