I got an "accept file transfer" window on my mac, what does it mean?

Question

I have no clue how anyone would be able to send me anything, but the window looked legit (definately not a pop-up) and then it disappeared. It asked me if I wanted to accept the file transfer of echo.m4a or something like that. It's never happened before and I've had my mac for a long time.

Answer 1

If you have no one sending you a file you know don't accept it.