Linux

Comprehensive Linux system administration guides covering processes, filesystems, kernel tuning, systemd, user management, and performance monitoring.

Networking

Linux networking guides: IP configuration, DNS, firewalls with iptables and nftables, routing, troubleshooting, DHCP, VLANs, and network bonding.

Security

Linux security hardening: encryption, SSL/TLS certificates, SSH hardening, firewall best practices, intrusion detection, SELinux, and server checklists.

Shell & Scripting

Bash and shell scripting tutorials: variables, loops, functions, sed, awk, regex, automation with cron and systemd timers, and modern shells like Zsh.

DevOps

DevOps for Linux: Git, Docker, Ansible, CI/CD pipelines, Kubernetes, Terraform, and backup strategies with rsync, Borg, and Restic.

Web Servers

Web server administration: Nginx, Apache, SSL/TLS setup, reverse proxy, load balancing, performance tuning, caching, and database administration.

VPN & SSH

VPN and SSH guides: WireGuard, OpenVPN, IPsec, SSH tunneling, port forwarding, rsync over SSH, SSHFS, and VPN protocol comparisons.

eSIM & Travel

eSIM guides, travel security, international data plans, digital nomad connectivity, securing devices abroad, and staying private while traveling.

Graphics & Web Design

Web design and graphics: SVG optimization, image formats, responsive design, CSS techniques, web fonts, accessibility, and performance for visual assets.

Unix Toolbox

The classic quick-reference for Unix/Linux commands. System, processes, networking, SSH, scripting, and more. Available in 6 languages.