Learn DOCKER in one Video | DOCKER Tutorial | DevOps Tutorial for beginners смотреть онлайн

Docker is container management tool. Starting with the basics of Docker which focuses on the installation and configuration of Docker. here we can pack our application as a image and run as a container.

we can reduce the cost of infrastructure with the container management tool. mostly we use containers in production environment

The prerequisite is that the readers should be familiar with the basic concepts of Windows and the various programs that are already available on the Windows operating system. In addition, it would help if the readers have some exposure to Linux.
Docker is a platform for developers and sysadmins to develop, deploy, and run applications with containers. The use of Linux containers to deploy applications is called containerization. Containers are not new, but their use for easily deploying applications is.

Containerization is increasingly popular because containers are:

Flexible: Even the most complex applications can be containerized.
Lightweight: Containers leverage and share the host kernel.
Interchangeable: You can deploy updates and upgrades on-the-fly.
Portable: You can build locally, deploy to the cloud, and run anywhere.
Scalable: You can increase and automatically distribute container replicas.
Stackable: You can stack services vertically and on-the-fly.
A container is launched by running an image. An image is an executable package that includes everything needed to run an application--the code, a runtime, libraries, environment variables, and configuration files.

A container is a runtime instance of an image--what the image becomes in memory when executed (that is, an image with state, or a user process). You can see a list of your running containers with the command, docker ps, just as you would in Linux.
Containers and virtual machines
A container runs natively on Linux and shares the kernel of the host machine with other containers. It runs a discrete process, taking no more memory than any other executable, making it lightweight.

By contrast, a virtual machine (VM) runs a full-blown “guest” operating system with virtual access to host resources through a hypervisor. In general, VMs provide an environment with more resources than most applications need.
Run docker --version and ensure that you have a supported version of Docker:

docker --version