The RAC is a British company that helps members when their car stops working on a journey. You pay to join; if the car breaks down, they send someone to fix it at the side of the road or to take it away. Its official name is RAC plc. The letters first stood for Royal Automobile Club, and you will still hear people say that in full — though actually the posh London club with that name and the roadside-help company later became separate businesses, so the van that rescues your car is not the same thing as the club. In Britain it is one of the two famous names for this kind of help; the other is the AA. It is a proper name, not a general English word for any car club. Taiwan does not use this company; the idea is the same as paying for roadside rescue.