The airtrain is the train that takes you from JFK to the Jamaaica Center Subway stop. From there, you can get on the E train into manhattan or go anywhere else on the subway system. The cost for the airtrain is $5 each way. If you buy the month long unlimited ride metrocard ($40), then the airtrain is only $1. There is no discount for the weekly metrocard. You can buy your airtrain and metrocards at JFK. There is also an airtrain that connects Newark airport to the New Jersey Transit train. This train is free. The new jersey transit train costs $12 and takes you from Newark airport (EWR) to New York Penn station in Manhattan.
