The concept

PCI-DSS, short for Payment Card Industry Data Security Standard, is the security standard maintained by the card networks that defines how card data must be collected, transmitted, processed, and stored by any company that handles payments.

A payment platform certified in PCI-DSS follows audited security controls, which reduces the risk of a card data breach for the buyers who go through your checkout.

How it shows up in practice

Your payment platform receives card data from all your international clients every time someone buys something. This data is card numbers, expiration dates, the buyer's CPF or ID. If this information leaks or falls into the hands of criminals, it's a disaster: your clients have cloned cards and you're left with legal responsibility. A PCI-DSS certified platform follows audited protocols to ensure nothing leaks.

Security is a process, not a product.

Bruce Schneier Source: Secrets and Lies: Digital Security in a Networked World.

Working with a certified platform dramatically reduces your legal and reputation risk. You don't store card data, don't process it directly, you just send it to the certified platform that does it safely. It seems invisible but it protects both you and your customers.