purge-docker.sh

# 1. Remove all containers including their volumes
docker rm -vf $(docker ps -a -q)

# 2. Remove all images
docker rmi -f $(docker images -a -q)

# (1) and (2) as an one-liner
export _DCKR=$(docker ps -a -q) && [ -n "$_DCKR" ] && docker rm -vf ${_DCKR[@]}; export _DCKR=$(docker images -a -q) && [ -n "$_DCKR" ] && docker rmi -f ${_DCKR[@]}; unset _DCKR

Cleanup unused networks: docker network prune