Brisbane is a major regional (in fact, national) transport hub, with an airport providing international and national connections; a large coach terminal with extensive connections, and a train station that provides connections to Sydney to the south, all the way along the coast to Rockhampton and Cairns to the north and (only twice a week), to Charleville to the west.
Within the city, the public transport is excellent. A completely integrated network is provided by TransLink, and combines an extensive network of buses, city trains and ferries, all covered by the same tickets.
The ticketing system is simple, with single fares as well as daily tickets (peak and off-peak). Peak hours are 2am to 9am and 3.30pm to 7pm on weekdays, which makes the daily off-peak ticket likely to be the best value for most visitors wishing to explore more during a day, but it's worth remembering that a single ticket is valid for two hours from the time of validation/purchase, for unlimited transfers between means of transport.
Brisbane ferries are particularly good value,connecting both sides of the river and allowing for a significantly cheaper alternative to a commercial cruise.