What is Docker?
Docker is a computer program that performs operating-system-level virtualization, also known as “containerization”. It was first released in 2013 and is developed by Docker, Inc. source: Wikipedia
How Docker works?
Docker containers wrap up software and its dependencies into a standardized unit for software development that includes everything it needs to run: code, runtime, system tools, and libraries. This guarantees that your application will always run the same and makes collaboration as simple as sharing a container image.
Docker unlocks the potential of your organization by giving developers and IT the freedom to build, manage and secure business-critical applications without the fear of technology or infrastructure lock-in. source: www.docker.com