Taint
In plain terms
A node property that repels pods unless they tolerate it.
Going deeper
A taint marks a node to prevent pods from scheduling there unless they have a matching toleration, controlling placement. It reserves nodes for specific workloads.
Under the hood
Paired with tolerations; used to dedicate nodes (e.g., GPU) or keep workloads off control-plane nodes.
Examples
Dedicated nodes, GPU scheduling, control-plane isolation, pod placement.
Think of it like...
Like a 'staff only' sign that keeps people out unless they have the right badge.