Payments 101

How card payments actually work

Six lessons in order, from the abstract to the concrete and from the happy path to the unhappy one. No endpoint appears in any of them — that comes after, in the journeys.

1. 01What is a card management system?The engine behind every card in your wallet — and what it actually does all day.4 min
2. 02The five players in every card paymentCardholder, merchant, acquirer, scheme, issuer — who does what, and where you sit.4 min
3. 03Life of a transaction: authorize, clear, settleWhy the money leaves in milliseconds but moves in days — the three phases of every payment.5 min
4. 04The life of a cardDesign → issue → activate → transact → renew — and the identifiers that follow the card everywhere.5 min
5. 05Limits, statements and installmentsHow credit room works, what a statement really is, and how EPP/IPP/BNPL turn purchases into plans.6 min
6. 06Declines, reversals and disputesThe unhappy paths — and why each one exists to protect somebody.5 min