Define ReplicaSets with atleast 2 example
Replica sets is to ensure defined no. of identical pods are always available, even if some of the pods gets corrupted and becomes unavailable, it is restarted by replica sets again.
In case of node failure where 1 node fails, replica-set ensure, pods of that node is started in another node.
In case of deployment rollout, replica sets ensure new pods gets created with new version.