I just started learning docker since a lot of online resources are free but I clearly am having difficulty understanding the “use case” for running containers in relation to how VMs are used. For example, my 1st project was to move my database off my raspberry pi. I’d like to run a docker container for my database but do I use an Ubuntu image to run a container and then customize the base image to handle my database or do I simply run the “postgres” image? I’d like to move my Pi-hole as well but do I run a debian image and install pi-hole or do I simply run the pi-hole image?
Yes, the best is you start with the official images (the images with no / in the name). For the beginning, you don’t have to care how they are built.