You can buy single and day tickets in advance at some ticket machines and kiosks as well as at other sales points and service points. The tickets are loaded on disposable cardboard cards.
When you start your first journey, show the card to a card reader on a bus, tram or train, or to a card reader at the top of escalators to the metro platform area. You only need to show the card to a card reader, you do not need to press any buttons. The reader makes a beep sound and the display shows the ticket information. You can check the expiry time of the ticket at any time by holding your card on the reading area.
The tickets are valid from the time you show the card to a card reader at the start of your first journey. After the first journey, you only need to show the ticket on buses. On trains and trams and on the metro, you only need to show your ticket if a conductor or ticket inspector asks you to do so.