Learn Basics Of Docker
Before understanding the Docker, let's discuss the basics of OS. Believe me, after clearing these basics you will be able to understand Docker very easily.
What is an os?
As you know, OS stands for operating system comes under the application layer. Not exactly, but It simply means a user interface that communicates with the hardware with the help of the kernel.
Now the question is, what is the kernel?
The kernel is the core or central component of an OS. It's just a piece of the software program that sits between the user interface and hardware. It provides the functionality to manage hardware and many other tasks that happen on the computer. It means to communicate between software and hardware.
Simply, it includes functions that are called while interacting with the OS and helps in the memory management, task management, disk management, etc.
Now, I assume you have understood the kernel; if not, please do research on it.
Now, we are at a good start to learn the Docker.
What is the Docker?
Docker, this is a software tool that eases the deployment process, delivers the application, and is responsible for running, stopping, or restarting the container.
To understand the above definition of docker, just move a little deeper into the docker definition.
Imagine you have a magical box that is the Docker. Now, instead of putting rabbit, hat, or pigeon, we are putting the required files and software for running the software. it keeps the required software and all other kinds of stuff (required libraries or settings, etc.) safe. So, no matter where you move this magical box, whether it's on your PC or your friend's PC, it will work same way. This magical box acts as a virtual machine. The main difference is that the virtual machine doesn't share the kernel(core component of OS), while this magical box shares the kernel. Now I hope you have understood the Docker.
Key component of docker:
Docker Engine
Docker Image
Docker Container
Docker Hub
Now we will discuss the component of the Docker
What is Docker Engine?
Imagine you have a magical box that can run any kind of software, no matter where you put it.
Now imagine this magical box is your docker engine. This is what exactly it is.
It is the core of the Dockers. It's a lightweight, portable runtime that runs containers and provides tools to build, ship, and run the container.
What is Docker Image?
Well, Docker Image is nothing but a blueprint or snapshot of the application and software, that is used to build and run containers. Docker image is built by using Docker file. A docker file is nothing but a text file in which required software and files are mentioned which is going to be used while building and running the containers.
What is Docker Containers?
It is an instance of an image. Simply, It means actual space or our magical box that includes required executable applications and software.
What is Docker Hub?
It is a cloud-based registry service where you can share and manage the Docker images. It includes the registry process through this registry process. Images are stored in Docker Hub, developer's can take pull this image to run the same application. Mainly, Docker Hub provides the feasibility to push and pull the Docker images by using the cloud-based registry.