In this chapter, we will explore authentication and authorization in Kubernetes, two critical mechanisms that secure access to your cluster. You’ll learn how Kubernetes verifies user identities through various authentication methods such as certificates, tokens, and external identity providers. We will then cover how authorization determines what authenticated users are allowed to do, focusing on mechanisms like RBAC (role-based access control), ABAC (attribute-based access control), Node, and webhooks. By the end, you will understand how to implement fine-grained access control to protect your cluster and ensure only the right users and services can perform specific actions.