Old vs new conventions
I was driving from Delhi to Jaipur yesterday night and one of the trucks in front gave right indicator and moved left and gave me side. Reminded me of old highway convention and how half of the Indian drivers are still following it.
In old days many 'highways' in India used to be a one lane road that was supposed to be used for traffic from both sides. There wasn't much automobile traffic and life was cool :) When the traffic increase these highways were upgraded to two lane highways where one lane was available for traffic going in either direction. Some readers will notice that most highways still fall in the two lane category though one can easily see four-laning of all major highways is in progress and some of the highways are already four lane.
Coming back to driving conventions on one or two lane highways. Blow horn and Wait for side were the most common slogans on the back of vehicles (It's a different point that the popularity of these slogans haven't decreased much). On one lane highways 'passing' a vehicle coming from other side meant taking one of your tyre on the shoulder and the other party would do the same. On both one way as well as two way highways overtaking was done with cooperation from the vehicle being overtaken (hence wait for side). Here is the whole process:
1. The vehicle interested in overtaking (Let's call it A) will blow horn (as requested by the vehicle in front; B for.)
2. B (or the driver) will check if another vehicle was coming from the other direction and signal with hand whether overtaking can be done. He would also signal if overtaking can not be done (though it was not mandatory)
3. A will follow B's suggestion and execute the overtaking maneuver.
Vehicle's were still manufactured with indicators that were used for turning and lane changing indications in rest of the world. In India lack of lanes (and hence lane changing) combined with 'cooperative overtaking' fueled the indicators being used as a signal to allow overtaking. As my smart readers will notice this is the exact opposite usage of the one originally intended.
On Indian highways both old Indian convention and the new convention (using indicators to signal lane change) are being used and one can't be sure if a right indicator means vehicle in front will move right or left :)
PS: I found hindi translation for word overtaking in Shimla. It's अभिलंघन :)