Ever growing scaling need demands for new architectural paradigms and technologies. Micro services are at forefront among distributed architectures in enterprises to meeting web scale needs. Micro services comes with its own mess of managing and updating them.
Containers such as dockers were introduced to package micro services deployments in predictable manner. Containers eliminate the needs for virtual machines. Managing containers need a container clustering mechanism. Kubernete is one of the top technologies to do just that. Docker swarm is an alternative for Kubernete.
Docker https://docs.docker.com/get-started/
Kubernete basics https://kubernetes.io/docs/tutorials/kubernetes-basics/