The Irish tend to drive their own cars, take a bus, call a taxi, ride their bike or hop on a train. Biking is a great way to get around Cork and there are even bike rentals in the city. There are many bike stations throughout the city where you can rent a bike and return it to any of the stations so you can rent a bike by your house and then bike downtown to work.
Ireland is an island and there are no bridges connecting it to Europe or the United Kingdom, so the only way to get to it is by airplane or ferry. The ferries that come to Ireland from the UK, Spain or France are huge and many people put their car on the boat with them. There are also smaller boats that go out to the smaller islands off of Ireland. A boat is one of the only forms of transportation that I have not used since being in Ireland, but I'm hoping to try it very soon.
Ireland is pretty small and is actually the size of a state such as Indiana. When driving you can get from one side of Ireland to the other in three hours. From the top of Northern Ireland to the south of the Republic of Ireland, it would take about six hours to drive. It takes me about three hours to get to the capital, Dublin, from Cork. To walk into the city center, it takes me about 20 minutes and the bus takes about eight minutes.