ffmpeg duplicates syntax. Except for the values used, and that the first command set the sampling rate instead of using the default, the commands are effectively the same:
-loglevel panic - merely makes ffmpeg less noisy in the shell
-vcodec copy = -c:v copy
-acodec copy -= -c:a copy # unlisted in the command, but listing here to show there is consistency
-ab = -b:a
Note: The other answer info is correct.
There is a guide online; it lists what every possible argument means.