American slang expressions often differ from standard British English terms. Some common differences include referring to having a "flat tire" instead of a "punctured tire", standing "in line" rather than "in queue", going to a "gas station" rather than a "petrol bunk", using a "period" rather than a "full stop", "mailing" a letter instead of "posting" it, "graduating" rather than "passing out", the "#" symbol meaning "pound" rather than "hash", turning "left at traffic lights or just lights" rather than "at the signal", being a "chicken" rather than "coward", saying "you bet" instead of other responses to "thank you",