Knowing the rules of the road is crucial, whether you've been on a driver for years or getting ready to sit your theory test . Road signs are an important part of safety, and one that crops up pretty much everyday. Road works might alert you of upcoming traffic, while most streets have specific speed limits. Now Annie, known as the Theory Test Practice on social media, alerted motorists what one triangular warning sign means. You might have spotted it in certain areas but it shows a car with