Kubernetes, Greek for “helmsman”, was announced by Google in June 2014. It drew on more than a decade of running containers at scale with Google’s internal Borg system. Version 1.0 shipped in July 2015, and Google donated the project to the newly formed Cloud Native Computing Foundation.
It quickly won the “orchestration wars” against Docker Swarm and Mesos, and every major cloud now offers a managed Kubernetes service. There are three minor releases a year, and the three most recent are supported, so each version gets about 14 months of patches. Planning cluster upgrades around those dates is a routine part of running Kubernetes.