Dear Road User,
Should you be located in the UK and in possession of an automobile, you may have noticed a strange lever positioned to the left of your steering wheel (the circular device which changes the direction of your car). If you are of the inquisitive sort you may have also discovered a causal relationship (or at least a very strong correlation) between pushing this appendage in either of the upwards or downwards directions, and the flashing of two sets of orange lights positioned down the sides of your car.
I'm here to assure you that this is a good thing and in no way the cause or result of black magic. The intention is that when you (the automobile operator) "turn" (to use the vernacular) you first activate one (but not both) of these sets of lights, thus apprising your fellow road users of your intentions. They would, of course, otherwise be forced to rely on telepathy. Telepathy is a dicey proposition at best, and one which should certainly not be attempted whilst simultaneously maneuvering around a ton of vehicular machinery. Contact of this sort with your cerebrum might also have the unfortunate side effect of causing them to "catch the stupid".
Do not forget: You are in Britain. To not follow these simple precautions is not just dangerous, worse, it is rude.
Cursing your Existence, That Last Roundabout.