Application Programming Interfaces (APIs) are a critical part of modern applications, enabling communication between services and applications. However, insecure APIs can expose sensitive data or functionality to attackers. API protection involves ensuring authentication, authorization, input validation, and encryption are consistently enforced across all endpoints. Rate limiting prevents abuse through brute-force attacks, while API gateways and monitoring tools provide visibility into usage patterns. Developers must also avoid exposing unnecessary endpoints and ensure that sensitive data is not returned in responses. As APIs are now common attack targets, protecting them is just as important as securing the application itself.