What command is used to list all Docker containers?

The command used to list all Docker containers is "docker ps -a." This command is specifically designed to display all containers, regardless of their current state. The "-a" option stands for "all," meaning that it will include containers that are running, stopped, or exited in the output. This comprehensive view allows users to see the complete status of their Docker containers, which is essential for managing and troubleshooting containerized applications effectively.

Other commands mentioned do not provide the same functionality. For instance, "docker list" is not an actual command in Docker; typically, users might confuse this with similar commands from other contexts. "docker show" is also incorrect as this command does not exist in Docker's command set. Lastly, "docker info" provides detailed information about the Docker installation itself—including version, storage driver, and number of containers—but it does not list individual containers. Therefore, understanding the use of "docker ps -a" is crucial for efficiently monitoring and managing Docker containers.