The taxi driver

Here's a joke that was emailed me:

A passenger in a taxi cab, needing to ask the driver a question, leaned forward and tapped him on the shoulder. The driver screamed, lost control of the cab, nearly hit a bus, drove up on the curb and stopped just inches from a large plate glass window. For a few minutes everything was silent in the cab. Then, still shaking, the driver said, "I'm sorry but you scared the daylights out of me." The frightened passenger apologized saying that he didn't realize a tap on the shoulder could be so scary. "No, no," said the driver. "It's all my fault. This is my first day driving a taxi. For the last 25 years I've driven a hearse."