The Toronto Transit Commission (TTC) is responsible for Toronto public transportation within the city limits. At the heart of the system is the Toronto Subway and RT consisting of three subway lines and one elevated light rail line. Streetcars, which operate on 11 routes are another major form of transportation in the downtown area and you haven't fully experienced Toronto without riding one. An extensive bus network connects these major modes of transit with the suburbs and outlying areas. Transportation beyond the city limits, but within the the GTA (Greater Toronto Area) is covered by other providers, however, most attractions that we cover are within the city. Go Transit, managed by Metrolinx, connects the city proper with outlying areas in the GTA and beyond (see below).
Individual fares only allow for a single trip in one direction (no round trips). If you expect to make more than 4 one-way trips in a single day,consider purchasing a day pass for $13.50 rather than one-ride or two-ride Presto tickets. It provides unlimited travel on all TTC routes within the city of Toronto except Downtown Express routes.
Besides the Toronto Transit Commission, Toronto is also served by Go Transit, a separate system of commuter passenger trains and connecting buses that not only operate from within the city of Toronto, but also extend into outlying regions of the GTA and beyond. Go Transit is a division of Metrolinx which is a crown agency of the Province of Ontario. Some of the neighbouring cities adjoining Toronto also operate their own bus systems, however these are not fully integrated with the Toronto Transit System and require separate fares or add fares. You can however, get to nearly all of Toronto's popular attractions using the TTC system. For more details about each aspect of the Transit system just click on the corresponding links above.
Official Website: http://www.ttc.ca/