What is the difference between image and container?

Image is a template with contains the application and its libraries and binaries
Container is a process with runs with the application from the image

How to check running containers?

docker ps -a command shows the running and stopped containers

How to create a new user in linux?

useradd command is used to create a new user with default user properties

What is sudo in linux?

run the command with the privilege of root user without root password

What does Docker run command do?

if the docker image is already in the local host, It will run the container else it will pull the image and run the container