My brother taught me a neat one-line trick today to clear up some extra harddrive space with docker prune.

It is pretty straight-forward:

docker image prune

What does this do? It searches through all the docker images you have locally on your computer and deletes any that don’t have any containers referencing them.

An image is like the saved docker instance and a container is an instantiation of an image. You may have multiple contianer objects for each image, but you may also have none.

This cleared up a couple gigs for me but I could se eit clearing up a lot more space for someone using docker more heavily.