An information system capable of utilizing information in which a user evaluation pertaining to the environment or conditions surrounding a traveling vehicle is highly precise (very near real time). The information system (100) comprises an onboard terminal device (110) for outputting information obtained by a user's input operation, a communication terminal device (120) for transmitting the information outputted by the onboard terminal device (110) to the exterior, and an information center (130) for classifying and delivering the information received from the onboard terminal device (110). The onboard terminal device (110) varies the level of detail of the information that the user is allowed to input in accordance with the speed of the vehicle or the presence/absence of a passenger other than the driver of the vehicle.