Objective of this article to explain about Docker Container and why do we need to use them.
What is Docker Container?
A Container is a standard unit of software packages up code and all its dependencies, so the application runs quickly and reliably from one computing environment to another. Docker is the container based, industry best software. Docker container is lightweight, standalone, executable package of software that includes everything needed to run an application such as code, runtime, system tools, system libraries and settings.
Container images become containers at runtime and in the case of Docker containers, image become container when they run on Docker Engine. Docker container that runs on Docker Engine,
Standard: Docker created the industry standards for Containers, so they could be portable anywhere.
Lightweight: Containers share the machine OS system kernel, so does not require OS per application.
Secure: Docker provides the strongest default isolation capabilities in the industry and applications are safer in containers.
Why do we need to use Docker Container?
As shown in the below diagram, there could be the dependencies between applications and its underlying software which is using to run. There could be many chances of raising problems with infrastructural and dependencies issues.
That’s where docker helps us to containerize each and every application into individual containers. Each individual container contains its dependent code, dependencies, system configurations, etc. So, they run any where.
If you observed the difference between above two images, image without Docker shown the common library and dependencies which is shared across multiple applications. Image with Docker will clearly shows that each individual docker container contains it’s libraries and Dependencies. So, with docker there is not chance of getting the problems related to libraries and dependencies and there is no chance of saying it works in my machine.