Docker is a containerization platform that allows you to quickly build, test, and deploy applications as portable, self-sufficient containers that can run virtually anywhere. It is used to create, deploy, and run applications by using containers.
For example, you can use Docker to package an application with all of its dependencies into a standardized unit for software development. This makes it easier to deploy the application on any server, regardless of the underlying architecture. Additionally, since the application is packaged into a container, it can be quickly and easily moved from one environment to another.