a PTC (push to console) are mostly basically commands built into game by the designer/programmers for their use (show FPS, tracers etc).
example of a ptc only hack:
the original relatively easy ptc method (devised by gellin) has been patched.
there are new ways to bypass this and still use the "PTC" functions with runconsolecmd addy and a gamestatus addy (needed otherwise you will d/c if you leave hacks on when a game ends..)
the commands are a function within the hack..
thats the best explanation i give because I am not a coder