Docker and Kubernetes serve distinct purposes in the realm of containerization and orchestration, although they are often used together. Docker is primarily a platform and tool designed for building, packaging, and deploying applications in containers. It allows developers to create isolated environments for their applications, ensuring that they run consistently across different environments by encapsulating all necessary dependencies. Docker focuses on creating single containers, managing their lifecycles, and providing a straightforward interface for interacting with them. In contrast, Kubernetes is a powerful orchestration platform that manages clusters of containers across multiple machines. It automates the deployment, scaling, and operations of application containers across clusters, facilitating seamless load balancing, rolling updates, and self-healing mechanisms that ensure the reliability and availability of applications.

While Docker can be seen as the standardized way to create and run containers, Kubernetes acts as a management layer that coordinates these containers at scale. When an application consists of multiple services, each running in its own container, Kubernetes abstracts the complexity of managing the underlying infrastructure, enabling developers to focus on application logic. It employs a declarative configuration model whereby users define how their application should behave, and Kubernetes ensures that the actual state matches the desired state. Thus, while Docker provides the tools for individual container creation and management, Kubernetes orchestrates and takes responsibility for the scalable deployment and operational continuity of those containers in a distributed environment.