Carjacking is a robbery in which a motor vehicle is taken over. In contrast to car theft, carjacking is usually in the presence and knowledge of the victim. A common crime in many places in the world, carjacking has been the subject of legislative responses, criminology studies, and prevention efforts. Commercial vehicles such as trucks and armored cars containing valuable cargo are common targets of carjacking attempts. Carjacking usually involves physical violence to the victim, or using the victim as a hostage. In rare cases, carjacking may also involve sexual assault.