Payment Systems

How payments really work, from zero: the machinery behind every transaction, what each player on the chain does, and how each one gets paid.

0. Payment Systems · The Course Map
1. The Nature of Payment: Money Never Actually Moves
2. Two Jobs Between Banks: Clearing and Settlement
3. The Hierarchy of Money: Whose Money Is Hardest?
4. The Origin of Cards: Solving Credit Between Strangers
5. The Four-Party Model: Why Visa and Mastercard Won
6. Interchange: The Economic Core of the Payments Industry
7. The Three-Phase Life of a Card Transaction
8. Card Not Present: A Thirty-Year Fraud Arms Race
9. Push and Pull: The Two Directions Money Moves
10. The Four US Rails, Side by Side
11. Push Rails Around the World: The Same Three Layers, Grown Differently
12. Domestic and Global: Fragmented at Home, Two Roads Across Borders
13. The Root Problem of Cross-Border: There Is No Global Central Bank
14. Inside a Remittance Message: What the Fields Decide
15. 欧元区清算轨道：四个问题看懂一条轨道 (not yet translated)
16. 中国清算轨道：多出来的那一层 (not yet translated)
17. 英国清算轨道：一个市场为什么长出四条 (not yet translated)
18. The Four Sources of Cross-Border Cost
19. The Wise Model: Cross-Border Remittances That Never Cross a Border
20. The Industry Role Map: Who Makes Money in the Middle
21. Case Studies: Nine Companies on the Grid
22. Neobank Anatomy: Where Your Money Actually Lives
23. The Five Risks of Payments
24. The Compliance Skeleton: Licenses, Identity, and Monitoring
25. Ledgers and Reconciliation: The Real Skeleton of a Payment System
26. What Stablecoins Are: Back to the Hierarchy-of-Money Table
27. What Stablecoins Solve — and What They Don't
28. Where CPN Stands on the Grid
29. The Final Review: One Question per Chapter
30. Agentic Payments: When the Payer Is No Longer Human
31. Frontier Radar: The Four Base Layers Being Replaced
32. Appendix A: The Four-Quadrant Solution Comparison