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run rst2myst, with minimal manual formatting fixes

docs/topic/whentouse.md

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+(topic-whentouse)=
+
+# When to use The Littlest JupyterHub
+
+This page is a brief guide to determining whether to use The Littlest JupyterHub
+(TLJH) or [Zero to JupyterHub for Kubernetes](https://zero-to-jupyterhub.readthedocs.io/en/latest/) (Z2JH).
+Many of these ideas were first laid out in a
+[blog post announcing TLJH](http://words.yuvi.in/post/the-littlest-jupyterhub/).
+
+[\*\*The Littlest JupyterHub (TLJH)\*\*](https://the-littlest-jupyterhub.readthedocs.io/en/latest/) is an opinionated and pre-configured distribution
+to deploy a JupyterHub on a **single machine** (in the cloud or on your own hardware).
+It is designed to be a more lightweight and maintainable solution
+for use-cases where size, scalability, and cost-savings are not a huge concern.
+
+[\*\*Zero to JupyterHub on Kubernetes\*\*](https://zero-to-jupyterhub.readthedocs.io/en/latest/) allows you
+to deploy JupyterHub on **Kubernetes**. This allows JupyterHub to scale to many thousands
+of users, to flexibly grow/shrink the size of resources it needs, and to use
+container technology in administering user sessions.
+
+## When to use TLJH vs. Z2JH
+
+The choice between TLJH and Z2JH ultimately comes down to only a few questions:
+
+1. Do you want your hub and all users to live on a **single, larger machine** vs. spreading users on a **cluster of smaller machines** that are scaled up or down?
+
+   - If you can use a single machine, we recommend **The Littlest JupyterHub**.
+   - If you wish to use multiple machines, we recommend **Zero to JupyterHub for Kubernetes**.
+
+2. Do you **need to use container technology**?
+
+   - If no, we recommend **The Littlest JupyterHub**.
+   - If yes, we recommend **Zero to JupyterHub for Kubernetes**.