Event data recorder (EDR) is a kind of equipment installed in cars, which is used to record information such as driving status, so as to provide evidence in traffic disputes. In modern diesel trucks, accidents often occur when the engine fails or the speed changes suddenly, and the driving recorder will record the data at this time. After the accident, the data collected from the driving recorder can be used to analyze the cause of the accident and determine the responsible person. This device is tamper-proof and readable, similar to a black box on an airplane. It is usually called "car black box" (not the same kind of equipment as tape recorders and cameras used in police cars).