Rancher is open source software that combines everything an organization needs to adopt and run containers in production. Built on Kubernetes, Rancher makes it easy for DevOps teams to test, deploy and manage their applications. Operations teams use Rancher to deploy, manage and secure every Kubernetes deployment regardless of where it is running.
If you haven't yet migrated to Rancher 2.x, you can still find documentation for 1.6 here. This is only for legacy users of the 1.6 product.
RancherOS is the lightest, easiest way to run Docker in production. Engineered from the ground up for security and speed, it runs all system services and user workloads within Docker containers.