Why is “Horn OK Please” painted on the back of almost every truck in India?

I am often asked this, i am not sure there is a definitive  answer but there are a few urban myths, here are a couple that i like… and whether they are right or wrong these colourful vehicles add a certain ‘he ne said quoi’ to the landscape

OK was a brand of detergent manufactured by Tata, and was publicised using trucks! It was painted in the centre, and became a standalone greeting, gesture, and exclamation.

The “Horn Please”, got split between Horn to the left and Please to the right, and if an OK was stuck in the middle, it became “Horn OK Please” and silly.

During the times when Indian highways were single lane, and you had to honk to indicate your intention to overtake, it would have been a bit safer to honk, for the driver of the vehicle ahead could caution you, usually by putting his hand out and waving slowly up and down if you can’t see an oncoming vehicle around the bend, or wave you ahead if the road was clear.

Another story i have been told is there is a little light to the right of the ‘OK’ , so when you come up behind the lorry on the road, and if it is a mountain road they really to crawl, you beep your honk and if it is clear to pass then the driver will light the light and you are good to go! Given the amount of dust on the roads I wonder how long the lights would be visible for!