GaN stands for gallium nitride and it is a semiconductor material that's replaced traditional silicon in modern chargers. GaN devices switch at much higher voltages and are quicker than silicon and generate less heat and providing more efficient electrical conversion. The payoff in real life is a charger that's significantly smaller than earlier 65W versions and that operates cooler and safer as well. The foldable plug design means you can simply toss it into your bag without the prongs scratching your laptop or sticking anything.