When told by ground control or tower that you are cleared to taxi, the controller has given you instruction to taxi along taxiway centerlines according to taxiway markings. It is important to repeat a [..]

ATC would like you to hurry up whatever it is that you're doing; taking off, landing, climbing, descending, or taxiing to your destination.

Followed by a squawk code or function button on the transponder. ATC issues individual squawk codes to all aircraft within radar service in order to differentiate traffic.