Shelves, books, pages

BookStack's content model is just three levels, and these docs use them deliberately:

Shelf   "Building a Kubernetes Platform on Proxmox"
  Book    "Kubernetes Cluster (kubeadm + Calico)"
    Page    "Joining the workers (and the firewall that blocked them)"

• Shelves are the big themes. This lab has two: the platform, and the core infrastructure under it.
• Books are topics — one coherent subject each (the cluster, the gateway, the registry…).
• Pages are the actual writing — ideally one idea each, short enough to read in a sitting.

A page belongs to a book; a book can sit on more than one shelf. That gentle structure is why you can land anywhere in these docs and still know where you are.

Why we use this: matching your content to the tool's structure is half of writing usable docs. "One idea per page, one topic per book, one theme per shelf" is a discipline that keeps documentation findable as it grows — which it always does.