API Gateway serves as a centralized entry point for accessing AWS services over HTTP, offering features like authorizers to secure API endpoints and prevent unauthorized access. Authorizers act as a security measure by verifying incoming requests before allowing them to reach the backend service, with options like JWT and Lambda authorizers providing different levels of flexibility and complexity. JWT authorizers utilize OpenID Connect Discovery endpoints to validate tokens, while Lambda authorizers allow custom code to determine request validity, supporting both REST and HTTP API Gateway types. Clerk's use of JWTs is compatible with API Gateway authorizers, enhancing security through session tokens, and enabling fine-tuned access control by modifying session tokens to include additional claims. The article explains how to configure both JWT and Lambda authorizers with Clerk, emphasizing the importance of securely managing API access to avoid risks like data exfiltration or unexpected AWS bills.