What is Docker

So, What is Docker?

Important: Writing this lines, I am not sure I can even consider myself a beginner, I actually know almost nothing about Docker/Containers and all the buzzwords around this world, but here's what I can say:

Docker and the concept of container is is actually a new level of virtualization of data, systems and services.

Just like every hypervisor we know allows to create multiple MACHINES on a single HARDWARE HOST,
Docker takes is to the software level.....
Docker is the method of building multiple systems to work on a single SOFTWARE HOST (this is the docker itself). 
And therefore, the equivalent of a Virtual Machine in Virtualization is the CONTAINER.
Container is the software add-on installed on top of the software HOST (base operating system)

But with one huge, significant, difference (advantage may I say?)

Container is build in LAYERS, which means multiple solutions can be built one on top of one another, all creating the desired environment we use in the end.

The idea Docker was built upon is to allow developers and people working in DevOps to very easily, very quickly, create lightweight development environment, with full flexibility.

Just like any other open-source system, docker is supported and integrated with DockerHub web-site - an images repository of probably everything you may ever need to create a single-layer or a multi-layered container, and of-course , an ever growing community.

In the docker area , you can find installation tutorials, preferably for Ubuntu, like:

• Installation of Docker
• Installation of Docker-Compose: the tool allowing to run multi-container applications.
• Installation of Portainer: our favourite web-based management environment.
• Suggested Images and packages
• Scripts and templates

etc....

Remember to visit this category , it will be constantly updated with new information and insights.