This chapter explores the architecture of Kubernetes, focusing on how its core components work together to manage containerized applications. It begins with an overview of the master node and worker node components, explaining their distinct responsibilities in scheduling, execution, and cluster management. The discussion extends to scalability, including strategies for handling large-scale clusters and example commands for cluster configuration. Special attention is given to etcd, the distributed key-value store, where the Raft consensus algorithm ensures consistency; practical examples show how pod metadata and other data are stored and retrieved. Cluster communication and high availability are also addressed, with sample commands illustrating how nodes maintain reliable interactions. The chapter concludes with a hands-on guide to setting up a Kubernetes cluster, integrating Docker, and troubleshooting common node issues. Together, these topics provide a clear understanding of the internal design, scalability, and operational resilience of Kubernetes clusters.