Because my memory fail me sometimes
- basics: introductory topics (bash, git, text manipulation)
- system: OS and hardware
- security: SSH, GPG, hardening
- storage: backups and disk management
- package: package tools & distro-specific guides
- scheduling: cron, systemd-timers
- advanced: specialization topics
- monitoring: logs & observability
- security_tools: tools such as OpenSSL, pass