Basic Kubernetes concepts
A cluster is a group of nodes; they can be physical servers or virtual machines that have the Kubernetes platform installed. The basic Kubernetes architecture is presented in the following diagram:

As you can see, the Kubernetes cluster consists of a Master node and a number of worker nodes with some components inside. While it may look scary and complicated at first glance, it will be easier to understand if we describe the concepts one by one, starting with the Pod.
Pods
The Pod consists of one or more Docker containers. This is the basic unit of the Kubernetes platform and an elementary piece of execution that Kubernetes works with. A diagram of the Pod is presented as following:

Containers running in the same Pod share the same common network namespace, disk, and security context. In fact, the communication over localhost is recommended between containers running on the same Pod. Each container can also communicate with any other Pod or service within the cluster...