Containers are similar to virtual machines with the exception of not having to install a separate operating system. This makes containers quick to implement and lightweight. Many more containers may exist on a physical server than virtual machines can. An application and all of the dependencies required for the application are stored in the container. In the following diagram, we can see how containers share an operating system through the use of a container engine:
Docker, an open source project first released in 2013, is one of the most popular container platforms on the market. Docker is available for all of the major operating systems including Windows, macOS, and Linux. A typical use of Docker is the development of WordPress websites for use in deployment to production environments. Check out www.docker.com for more information and documentation.
Containers may be easily moved from machine to machine, hence allowing a developer to create an application on a development machine and port it to a hosting machine without the worry of compatibility issues.