E-ZPass is an electronic toll collection system used in the United States of America. It utilizes transponders which are issued by a number of entities. You are not required to use the responders provided by the state in which you live, you are free to use transponders from any of these entities. Some tolls are discounted, either for all transponders, or for transponders issued by a specific entity. Also, entities have different fee schedules and minimum balance requirements. This site provides the information you need to make an informed decision about which transponder is best for you, based on how much and where you drive.