Luas
www.luas.ie

This is the tram which has two lines, one going west and one going south through the city. The red line is probably the handiest for tourists as it can get you to the main bus and train stations, the Guinness Storehouse, Kilmainham and some museums. It is very reliable and comes approx every 5 minutes. You buy a ticket from the machine at the stop and there is usually inspectors on the tram to check them.