Container templates
A template is the starting point for an LXC container (abbreviated in Proxmox VE as "CT"). There are two sorts of templates: OS templates and appliance templates.
OS templates provide a minimal set of packages from a GNU/Linux distribution, as well as system libraries and scripts, to start up and run the container. They're designed to benefit fully from the GNU/Linux kernel running on the host.
Aside from basic tools, such as a bash interpreter and utilities, additional software, such as a compiler or a DBMS is not usually incorporated into an OS template.
In contrast to OS templates, virtual appliances are built on top of JeOS (Just enough Operating System) to provide a very specific service reliably, securely, and with an absolute commitment to efficiency.
Virtual appliances can provide general functionality, such as LAMP stack; or a specific application, such as GitLab (https://about.gitlab.com/); a CMS such as WordPress or Drupal; or a web-based network monitoring system...
