This document discusses mass transit systems. It defines mass transit as public shared transportation like trains and buses that can transport many passengers from one location to another in less time without reservations. There are three types of mass transit based on right of way: category A systems have exclusive paths like metro rail, category B are partially separated like bus rapid transit, and category C mix with other vehicles like regular bus systems. The document outlines advantages of mass transit such as reduced pollution, traffic, and fuel costs compared to individual transportation. It also saves money, time, and improves safety and public health.