Introduction to Docker – Why Every Developer Should Know It

Definition

Docker is a platform that uses OS-level virtualization, also called containerization.
Instead of creating a full virtual machine or installing a separate OS, Docker lets applications share the host OS kernel.

This makes containers:

• Lightweight

• Faster to start

• Easy to move between different environments

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Why Docker?

Before Docker, a common conversation between developers and QA teams used to be:

“It works on my system, but not on the server.”

These issues often happened because of missing configurations or dependencies in the deployment environment.

Docker solves this problem by:

• Packaging the application code

• Including all required configurations

• Bundling every dependency into one container

So wherever you run it — your laptop, a test server, or in the cloud — the container behaves the same.

In short: if it runs in a container once, it will run anywhere.

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👉 Next Blog Teaser: In the next part, I’ll cover what are all the components of the Docker Stay tuned! 🚀