A GoCard is an electronic money card, the same size as a credit card, that fits in your wallet. You can put money on it by paying cash, in lumps of $10, to a bus driver or GoCard agent and they will tell their electronic ticket machine to zap the amount on to your card.
Leave it inside your walletEdit
You don't have to take your GoCard out of your wallet. The ticket machine can "talk" to your card with radio signals which can penetrate through the thickness of your wallet and its contents while your wallet is resting on the ticket machine.