The Presto system allows passengers to load a reloadable card with any amount starting at $10, up to $1,000. Passengers pay their fare by "tapping" on and off on busses and trains. With each tap, the system calculates the fare for the ride, and it is deducted from the balance of the card. The card can also be linked to a credit card and set on autoload, so that it automatically adds a certain amount of money as soon as the balance decreases past a certain level (e.g., setting it to add $100 every time the balance decreases to less than $25).