Docker

Docker packages applications and dependencies into containers — portable, isolated environments that run consistently from laptop to production.

Source

• Docker documentation
• What is Docker?

Why Docker

Benefit	Detail
Consistency	Same image in dev, CI, and prod
Isolation	Processes share the host kernel, not a full VM
Speed	Lightweight starts vs hypervisor VMs
Ecosystem	Dockerfile, Compose, Hub registries

Core concepts

• Image — read-only template (layers from Dockerfile instructions)
• Container — running instance of an image
• Registry — image storage (Docker Hub or private)
• Compose — multi-container apps via docker-compose.yml

Quick example

docker run -it --rm ubuntu /bin/bash

In this section

• Run docker without sudo
• MultiArch Builds

Related

• Containerisation
• Kubernetes