Linux

The operating system underneath most servers and cloud infrastructure.

CurrentintermediateFull course available

Overview

Linux is the operating system running the vast majority of servers, cloud infrastructure, and containers. Comfort with its filesystem layout, permissions model, and process management is assumed by nearly every deployment, DevOps, or backend-operations task.

What it is
An open-source Unix-like operating system, dominant on servers and cloud infrastructure.
Why it's used
It's free, stable, and the near-universal choice for servers -- most cloud VMs and containers run some Linux distribution.
Where it fits
The operating system underneath servers, Docker containers, and most cloud infrastructure -- Bash is typically the interface to it. The Linux and Shell Fundamentals course covers user-space Linux literacy in depth: the filesystem model, permissions and ownership, processes and signals, and safe, automation-oriented command-line workflows -- explicitly not a system-administration certification course.

Core concepts

  • The filesystem hierarchy
  • File permissions (chmod, chown)
  • Processes and signals
  • Package managers (apt, yum)

Example

File permissions (chmod 644) and process inspection (ps) are basic but essential Linux literacy for anyone deploying or debugging a server-side application.

chmod 644 config.json   # owner: read/write, others: read-only
ps aux | grep node       # find running node processes

Common use cases

  • Server administration
  • Deploying and debugging containerized applications
  • General cloud/DevOps work

Project ideas

  • Set up a small Linux VM (or WSL/container) and practice navigating, setting permissions, and running a simple server

Official references