PCI compliance means meeting the security requirements of the Payment Card Industry Data Security Standard (PCI DSS) to protect cardholder data and the systems that store, process, or transmit it. It matters because payment environments are high-value targets: weak access controls, exposed databases, or poorly monitored changes can lead to card theft, fraud, and costly incidents.
In practice, PCI compliance pushes defenders to harden networks, restrict access, encrypt sensitive data, and keep systems under continuous review. File integrity monitoring is one common control because it can detect unauthorized changes to payment servers, configuration files, and security tools. For example, if malware or an insider alters a checkout application or logging setting, monitoring may reveal the change before it is used to steal data or hide activity. Compliance does not stop attacks by itself, but it creates measurable security baselines and evidence that controls are operating consistently.