What is Docker?

Wait a minute, even before this:

What are containers and images?

To simplify, think of Docker Images as the recipes we consult before preparing a dish. A recipe includes a list of ingredients, step-by-step instructions, and even special techniques required to achieve the perfect outcome. Similarly, a Docker Image is a meticulously crafted blueprint that contains everything needed to run an application—from the base operating system and essential libraries to the application code, dependencies, and configuration files. It's a self-contained unit that ensures consistency across different environments.

Now, imagine you're following the recipe to cook a dish. The final, delicious meal on your plate is akin to a Docker Container. Just as a dish is the tangible result of following a recipe, a Docker Container is the running instance of an image—a live, breathing environment where your application is executed. Containers are the manifestation of the image's potential, providing an isolated, secure, and consistent environment that can be easily replicated or scaled across various systems.

In essence, Docker Images lay down the blueprint, while Docker Containers bring that blueprint to life, allowing you to build, test, and deploy applications with unparalleled efficiency and reliability.

https://www.google.com/url?sa=i&url=https://www.reddit.com/r/ProgrammerHumor/comments/zg4wso/you_should_use_docker_its_so_light_weight/&psig=AOvVaw0Cl_Ni-1xOQGQ9Oek1Bw_Q&ust=1724504018197000&source=images&cd=vfe&opi=89978449&ved=0CBQQjRxqFwoTCNDW1pqUi4gDFQAAAAAdAAAAABAE

Binding it up,

Docker is a platform for building and running containers. Containers are software units that package source code and its dependencies inside isolated environments. They’re usually ephemeral, with the contents of a container’s filesystem disposed of when it stops, but you can also store data persistently using features such as volumes.

And now you know that what Docker is?

So, let me tell you what used to happen before Docker existed. Whenever a company needed to scale, or even build and deploy more applications alongside the existing ones, they would have to buy new servers, configure them, and set everything up. And the next day, if there were new applications, they needed new servers again... new day, new servers.….and the cycle continued. Notice something here?

Yes, the cost—the escalating cost of buying new servers, maintaining them, and ensuring they were always up and running. On top of that, the system administrators had their hands full managing this infrastructure, dealing with compatibility issues, and making sure everything was deployed correctly. It was a constant headache, like chasing after something that was always just out of reach.

But then, Docker comes into the picture.

Our hero, Docker, steps in and says, "I will run your applications without requiring you to install heavy packages and software for compatibility. You don’t need to worry about configuring entire servers or buying new ones. I have something called the Docker Engine that can isolate and run your applications seamlessly in lightweight containers, no matter where they are deployed."

With Docker, you can package everything your application needs into a single, portable image that runs reliably on any environment with Docker installed. This dramatically reduces the overhead, simplifies the deployment process, and makes scaling applications as easy as spinning up more containers—no more headaches, just efficiency and scalability.

Ok now, Let’s get onto Handsonn

Basic Docker Commands and Their Use Cases

1. docker pull [image_name]

Use Case: