…Remind me what that means?!

Tap On, Tap Off is one of several names given to the type of contactless payment method that allows you to simply “tap” your contactless payment card (or device) onto a reader at the start of your journey and “tap” again on a reader when you complete your journey. What you are charged for the journey is calculated later and then automatically from your account. Often this charge will be capped at a maximum amount if enough journeys are taken within a specific period of time, e.g. a day.