Docker Commands You Must Know – Quick Guide for Beginners

Essential Docker Commands – Quick Reference Guide

A concise collection of commonly used Docker commands with one-line explanations, designed for quick revision, daily usage, and interview preparation.

 docker --version                             # shows Docker version

docker version                               # shows client and server version info

docker ps                                    # lists running containers

docker ps -a                                 # lists all containers

docker container ls                          # lists running containers (modern syntax)

docker container ls -a                       # lists all containers (modern syntax)

docker images                                # lists all Docker images

docker image ls                              # alternative command to list images

docker images -q                             # shows only image IDs

docker pull ubuntu                           # pulls ubuntu:latest image from registry

docker pull ubuntu:22.04                     # pulls specific image tag

docker run ubuntu                            # creates and runs a container

docker run -it ubuntu bash                   # creates interactive container with shell

docker run -it --name cont1 ubuntu bash      # creates and runs named container

docker run -d ubuntu sleep infinity          # runs container in background

docker create ubuntu                         # creates container without starting

docker start cont1                           # starts a stopped container

docker start -i cont1                        # starts container and attaches terminal

docker ps -q                                 # shows running container IDs

docker ps -aq                                # shows all container IDs

docker exec -it cont1 bash                   # opens a new shell inside running container

docker attach cont1                          # attaches to main container process

docker stop cont1                            # gracefully stops container

docker kill cont1                            # force stops container

docker pause cont1                           # pauses container processes

docker unpause cont1                         # resumes paused container

docker rm cont1                              # removes stopped container

docker rm -f cont1                           # force removes running container

docker rm -f $(docker ps -aq)                # removes all containers

docker rmi image_name                        # removes an image

docker rmi -f image_name                     # force removes an image

docker rmi -f $(docker images -aq)           # removes all images

docker image prune                           # removes unused images

docker container prune                       # removes stopped containers

docker system prune                          # removes unused containers, images, networks

docker build -t myimage .                    # builds image from Dockerfile

docker commit cont1 myimage:v1               # creates image from container state

apt update                                   # updates package lists inside container

apt install -y python3                       # installs Python 3 inside container

apt install -y apache2                       # installs Apache inside container

apt install -y mysql-server                  # installs MySQL inside container

apachectl -D FOREGROUND                      # starts Apache in foreground

service apache2 start                        # starts Apache service