You get a device (like those in the pictures), which you then connect to your computer, and insert your debit card. When you do an online operation (e.g. bank transfer), the bank site requires the transaction to be digitally signed by your card (and which requires your PIN).
Ah OK I didn't look closely enough as I thought the picture were of POS terminal devices. I was confusing CAP with "chip and pin" - the tech used inside debit cards.