Docker is a platform for packaging, deploying, and running applications. Docker applications run in containers that can be used on any system: a developer’s laptop, systems on premises, or in the cloud. Containerization is a technology that’s been around for a long time, but it’s seen new life with Docker. It packages applications as images that contain everything needed to run them: code, runtime environment, libraries, and configuration.

Containers are portable assets that let you design and deploy with little overhead from your development team. They take your monolithic code base and turn it into several lightweight modules that you can more easily manage and interconnect without worry of one small module taking out your entire application. This gives you more granular control of your code, but it also means that you have several moving parts as part of your platform.