granted yellow is more common in fog lights, there still are some white.
The main difference is the beam the light projects.
A fog light sends a short and wide beam, while a driving light projects a long and narrow beam.
Driving lights are technically supposed to be auxillary to your high beams, while fogs are to your lows.
Most factory "fogs" go off when you hit your high beams because if there was fog, you'd be worsening your vibility by increasing the glare.
People that hook up their driving lights to the factory wiring are missing out. Driving lights are "SUPPOSED" to be on with high beams, while running them off the factory switch and wiring shuts them off when the high beam kick in.
My personal favorite is still driving lights
2004 Torch Red Coupe
2001 Pontiac Bonneville SSEi - 103,000 miles - Galaxy Silver - Daily Driver
1994 Pontiac Bonneville SE - 209,000 miles - Light Gray Metallic - SOLD