Now to the purpose of the Ground controller.
The ground is basically responsible for traffic on the ground. He will give clearance for pushback from the gate and taxi instructions. He can give clearance to cross inactive runways but the pilot must contact tower to cross active runways.
After the pilot has contacted clearance delivery and recieved his flight plan, he will contact ground for pushback and taxi instructions to the runway.
Pilot: Nor-Shuttle 5528 ready for taxi!
Atc: NAX5528 taxi and hold short of runway 26R via taxiway Lima, Oscar and Yankee
Pilot: Taxi to runway 26R via taxiway Lima, Oscar and Yankee , NAX5528
Pilot: Easy334K at gate 24 requesting taxi!
ATC: Easy334K taxi to runway 34 using taxiway H H2 B, holding point H8
Pilot: taxi to runway 34 using taxiway H H2 B, holding point H8, Easy334K
A Holding point taxiway is where the pilot most stop his plane. There will (should be) a thick yellow line stretching the width of the taxiiway together with a holding point sign.
Sometimes the ground will tell the pilot to just follow another aircraft to the runway. Ensure you maintain a minimum of 30metres from that traffic
If there are a lot of taxiways the ATC might tell the pilot to taxi and then hold short on a crossing taxiway for further instructions so it will be more easy for the pilot.
It’s required of the ground to keep communicating with the tower for active runways so there won’t be any confusions for the pilots.
You may hear a controller occasionally say “Taxi stand of your choices via taxiways of choice”. This will be because the taxiway lay out will be too complicated for the pilot to work out in a short time. If you hear this command, simply taxi to a stand of your choice via any taxiways. Remain vigilant and keep the speed down, the controller will still be monitoring you.