When we talk about packages, we generally refer to scalable aggregated blocks of software or libraries. In fact, a package can be used by multiple applications by importing or extending the package itself. Docker is a tool that will make your life as a developer easier. We are talking about an open-source project that can automate the deployment of applications inside software containers; in essence, a platform that will enable you to create, test and distribute applications via containers. Docker Package: the concept of “image” The concept of package can be thought of as ‘Docker with images’, or Docker image..