One of the first things visitors notice...

the colorful taxi cabs.

We have bright pink, green, blue, orange, yellow, purple, red, and multicolored taxis in Bangkok. The color signifies the company and also makes them easy to spot when you're looking for a ride. I have a Thai friend who will only ride in certain color taxis because he says the others smell bad, but they all have that mixed taxicab smell to me.