Docker

Docker is a platform that simplifies running apps by using containers. Containers package your app with everything it needs—code, libraries, dependencies—into one self-contained unit. This ensures your app runs consistently no matter where it’s deployed, solving the “it works on my machine” problem.

Why Containers?

Traditional apps rely on the host machine’s operating system and configurations. This can cause issues if environments differ between development, testing, and production. Containers isolate your app from the host machine, bundling its own operating system environment, so the app behaves the same anywhere it runs.

How Docker Works:

• Images: Docker uses images as blueprints for containers. An image includes the app’s code, required dependencies, and an operating system (usually lightweight).
• Containers: When you run an image, Docker creates a container—a running instance of the image. Each container is isolated from others, preventing conflicts.
• Registry: Docker use so called “registries” to store theses images. Docker Hub is the official public repository where developers can find and share pre-built images (e.g., nginx, node, or custom-built ones). Anyone can also host their own registry.

Why Use Docker?

• Consistency: Works across any environment (local, staging, production).
• Isolation: Prevents conflicts between different apps or dependencies.
• Lightweight: Containers share the host OS’s kernel, making them more efficient than virtual machines.
• Portability: Easily move apps between different platforms or clouds.

By using Docker, developers can streamline deployment, testing, and collaboration across teams without worrying about environment issues.