I'll see if I can pretty much get these definitions straight for ya.
Crisp..there is a thread already posted on what a "crisp" trigger pull feels like, but basically its a pull like breaking a small glass rod, just a clean break that comes as more of a surprise than anything.
Creep..When pulling a trigger to the rear in single action mode, some weapons have a slightly mushy feel, or a feeling where you can feel the sear starting to realease, but it does not release cleanly. Basically, "creeping" until it finally releases.
Travel..This is the distance a triger moves in double action or single action before the sear finally releases. Some autos, like Browning HP's have a trigger "travel" of approximately 1/4 inch with slight spring resistance, but no sear engagement before coming to a point where actual pressing the trigger will fire the weapon. Others like Glocks use trigger travel to move a striker back, much like moving the hammer on a DA type weapon, but much lighter.
Takeup.. Much like the Browning HP I described above, with an amount of free trigger movement prior to actually firing the weapon. In a Glock this can be described as the point where you feel the trigger loading up with spring pressure until you finally hit a "wall", a point where you know exactly when the weapon will fire. Many DA/SA Autos have an amount of freeplay in the trigger when firing in SA mode, with no resistance for anywhere from 1/4 to 1/2" before actually getting to the point where there weapon will fire.
I'm sure there are many explanations, some much better than mine, but this is the best I know to describe these terms
Good SHooting
RED