Kubernetes Cluster
A Cluster is a group of Nodes that are managed together by a (sidenote: A single node that acts as the so-called leader. Instructing which pods etc. should run on which nodes.) node.
Kubernetes clusters make use of a set of API’s that controls the different nodes and makes sure the system is in sync.
A cluster leverages the ability to control several nodes on different (sidenote: Usually, these machines are in different physical locations.) to ensure rendundancy.