What is lane departure warning?

Lane departure warning is a fairly self-explanatory name for a modern car safety system. It's designed to warn you if you start to drift out of your lane. On-board cameras scan the road ahead to identify where the lane lines are. From this, the car can detect any time you drift outside those lines. If the car thinks you've crossed a lane line unintentionally – especially if you don't have your indicator turned on – it'll beep at you and turn on a flashing light in the driver's dials to alert you to the risk. A more advanced version of this system is called lane-keep assist, which will actually steer the car back into line by itself if you fail to respond to warnings.