Linux powers the overwhelming majority of the world's servers, cloud infrastructure, containers, and DevOps tooling. When you deploy an application to AWS, Azure, or Google Cloud, it almost certainly runs on a Linux kernel. When you launch a Docker container, it shares the Linux kernel of the host machine.
Understanding Linux is not an optional extra for a DevOps engineer — it is the foundational layer beneath every tool in the profession. Without it, commands fail in ways you cannot diagnose, scripts behave unpredictably, and production incidents become opaque puzzles. Every subsequent skill in this course — Docker, Kubernetes, Terraform, CI/CD — rests on Linux fluency.
Analogy🏏Cricket
🏏 Think of it like cricket: The match itself is the kernel — real computation at the hardware level. The commentators translating that action into words for the audience are the shell: they take raw events and present them in a form humans can understand and interact with. The television set in your living room is the terminal emulator: it displays the commentary but does not participate in the match.Just as switching from one broadcaster to another changes commentary style but not the underlying match, switching between Linux distributions changes shell defaults and package manager but not the kernel. Just as Star Sports and Sony Six both cover the same IPL match with different graphics packages, Ubuntu and Alpine both run the same kernel with different userspace tools.The insight is that these layers are genuinely separate, which is why you can swap any one of them independently.