Operating Systems

This section covers platform-specific fundamentals for Debian, OpenBSD, and Arch Linux.

Each operating system is presented on its own terms—from package management and release models to system architecture. Rather than comparing distributions, the focus is on understanding how each system works and the design decisions behind it.

General Unix concepts are covered in the Cross-Platform Fundamentals, including filesystem hierarchy, networking fundamentals, init systems, and package management concepts.

Available Series

Debian Fundamentals

📋 Series planned: Release model, APT/dpkg architecture, systemd integration, and Debian security concepts.

Coming soon

OpenBSD Fundamentals

📚 Series available: Secure by Default, the pf firewall, rcctl service management, pledge, unveil, and OpenBSD system architecture.

Explore Series

Arch Linux Fundamentals

📋 Series planned: pacman, the Arch User Repository (AUR), PKGBUILD, and the rolling release model.

Coming soon

Platform-Specific Topics

Debian

APT/dpkg architecture, repository structure (main, contrib, non-free), Stable/Testing/Unstable, unattended-upgrades, and systemd integration.

OpenBSD

pkg_add, the Ports Collection, the pf firewall, rcctl service management, and sysmerge for configuration updates.

Arch Linux

pacman, the Arch User Repository (AUR), PKGBUILD, rolling releases, and systemd-based service management.

Related Fundamentals

• Linux/Unix Filesystem
• Network Fundamentals
• Init Systems
• Package Management Concepts

Status: October 2025 — The OpenBSD Fundamentals series is available. Debian and Arch Linux are currently in development.