docker clean up container records

Here is the Ubuntu linux system;

Step 1 : View all containers:
Type:

docker ps -a

show:

root@iZ2ze0zuq27nx0z96tt9:~# docker ps -a
CONTAINER ID   IMAGE         COMMAND                  CREATED         STATUS                        PORTS                                                  NAMES
0f7de3d8c822   mysql         "docker-entrypoint.s…"   12 months ago   Exited (255) 31 minutes ago   0.0.0.0:3306->3306/tcp, :::3306->3306/tcp, 33060/tcp   docker_mysql
f4bcbbac5378   hello-world   "/hello"                 14 months ago   Exited (0) 14 months ago                                                             zealous_matsumoto

Supplement: Command:
docker ps: return running containers;
docker ps -a: return all containers (including Exited containers);

Step 2 : Remove unused containers:
Type:

 docker rm -f f4bcbbac5378

Where f4bcbbac5378 is the container number. show:

root@iZ2ze0zuq27nx0z96tt:~# docker rm -f f4bcbbac5378
f4bcbbac5378

Returning the container ID indicates that the deletion is successful.