Docker is a set of platform as a service products ( PaaS)  that use OS-level virtualization to deliver software in packages called containers.  Developers can build, share, and run modern applications using docker.

Here are top 20 most used docker commands that you must know.

1. docker version

Displays the Docker version information.
Example: To display the Docker version information in your terminal, run the following command:
docker version

2. docker search

Searches the Docker Hub registry for an image.
Example: To search for the nginx image on Docker Hub, run the following command in your terminal:
docker search nginx

3. docker pull

Pulls an image from a registry to the local machine.
Example: To pull the nginx image from Docker Hub, run the following command in your terminal:
docker pull nginx

4. docker run

Runs a command in a new container.
Example: To start a new container using the nginx image and map port 80 of the container to port 8080 of the host, run the following command in your terminal:
docker run -p 8080:80 nginx

5. docker ps

Lists the running containers.
Example: To list all the running containers on your system, run the following command in your terminal:
docker ps

6. docker stop

Stops one or more running containers.
Example: To stop a running container with the ID 123456, run the following command in your terminal:
docker stop 123456

7. docker restart

Restarts one or more containers.
Example: To restart a container with the ID 123456, run the following command in your terminal:
docker restart 123456

8. docker kill

Sends a SIGKILL signal to a running container, killing it.
Example: To kill a running container with the ID 123456, run the following command in your terminal:
docker kill 123456

9. docker exec

Runs a command in a running container.
Example: To run a command ls inside a running container with the ID 123456, run the following command in your terminal:
docker exec 123456 ls

10. docker login

Logs in to a Docker registry.
Example: To log in to Docker Hub, run the following command in your terminal:
docker login

11. docker commit

Creates a new image from a containers changes.
Example: To create a new image from a container with the ID 123456, run the following command in your terminal:
docker commit 123456 myimage:v1.0

12. docker push

Pushes an image to a registry.
Example: To push the myimage:v1.0 image to Docker Hub, run the following command in your terminal:
docker push myusername/myimage:v1.0

13. docker network

Manages Docker networks.
Example: To create a new network called mynetwork, run the following command in your terminal:
docker network create mynetwork

14 docker history

Shows the history of an image.
Example: To display the history of the nginx image, run the following command in your terminal:
docker history nginx

15. docker rmi

Removes one or more images.
Example: To remove an image with the ID 123456, run the following command in your terminal:
docker rmi 123456

16. docker ps -a

Lists all containers, including stopped containers.
Example: To list all the containers, including the stopped ones, run the following command in your terminal:
docker ps -a

17. docker copy

Copies files or folders between a container and the local filesystem.
Example: To copy a file myfile.txt from a container with the ID 123456 to your local filesystem, run the following command in your terminal:
docker cp 123456:/path/to/myfile.txt /path/to/destination

18. docker logs

Shows the logs of a container.
Example: To show the logs of a container with the ID 123456, run the following command in your terminal:
docker logs 123456

19. docker volume

Manages Docker volumes.
Example: To create a new volume called myvolume, run the following command in your terminal:
docker volume create myvolume

20. docker logout

Logs out from a Docker registry.
Example: To log out from Docker Hub, run the following command in your terminal:
docker logout