website/content/en/docs/reference/glossary/affinity.md

title	id	date	full_link	short_description	aka	tags
Affinity	affinity	2019-01-11	/docs/concepts/scheduling-eviction/assign-pod-node/#affinity-and-anti-affinity	Rules used by the scheduler to determine where to place pods		fundamental

In Kubernetes, affinity is a set of rules that give hints to the scheduler about where to place pods.

There are two kinds of affinity:

• node affinity
• pod-to-pod affinity

The rules are defined using the Kubernetes {{< glossary_tooltip term_id="label" text="labels">}}, and {{< glossary_tooltip term_id="selector" text="selectors">}} specified in {{< glossary_tooltip term_id="pod" text="pods" >}}, and they can be either required or preferred, depending on how strictly you want the scheduler to enforce them.