<p>In Kubernetes <em>POD</em> is considered as a single unit of deployment which might have one or more containers, so if we scale all the containers in the <em>POD</em> are scaled irrespectively. </p>

<p>If the <em>POD</em> has only one container its easier to scale the particular <em>POD</em>, so whats purpose of packaging one or more containers inside the <em>POD</em>?</p>

<p>From the <a href="https://kubernetes.io/docs/concepts/workloads/pods/pod/#uses-of-pods" rel="noreferrer">documentation</a>:</p>

<blockquote>
  <p>Pods can be used to host vertically integrated application stacks (e.g. LAMP), but their primary motivation is to support co-located, co-managed helper programs</p>
</blockquote>

<p>The most common example of this is sidecar containers which contain helper applications like log shipping utilities.</p>

<p>A deeper dive can be found <a href="https://kubernetes.io/blog/2015/06/the-distributed-system-toolkit-patterns/" rel="noreferrer">here</a></p>
