The principle of deploying software with containers is very simple: the software, plus everything it needs to run, is inside the container image, which is like a package file, but is executable directly by the container runtime.
To run the software, all you need to do is execute a command like the following (if you have Docker installed, try it!):
docker run bitfield/hello
Hello, worldDocker will download the specified image from your configured registry (this could be the public registry, called Docker Hub, or your own private Docker registry) and execute it. There are thousands of Docker images available for you to use, and many software companies are increasingly using Docker images as their primary way to deploy products.