This section provides an overview of deploying igweb as a multi-container Docker application on the Linode cloud. Docker is a technology and a platform that allows us to run and manage multiple Docker containers on a single machine. You can think of a Docker container as a modular, lightweight virtual machine. We can make an application, such as igweb, instantly portable by packaging it as a Docker container. The application is guaranteed to run the same way inside the container, regardless of which environment it is run on.

Most cloud providers offer support for Docker making it a very handy tool for cloud-based deployments. As you will see later in this chapter, deploying a multi-container Docker application on the Linode cloud is relatively easy.