What is Linux? 
▍ https://img.devrant.com/devrant/rant/r_1578772_VbG6J.jpg | Icons by flaticon.com 4 / 14
Introduction to Linux: Overview
Philipp Fruck & Pius Walter Introduction ██ About us ██ About you
• Pius & Philipp Quickly introduce yourself:
• Studied CS back in 2019 • First time lecture this year • Who are you?
◦ We need your feedback! • Which Operating Systems did you use
previously ◦ Windows, MacOS, Linux? Or only mobile devices? 2 / 14 Organizational • 5 lectures between 2 and 4.5 hours • Mostly hands-on ◦ You'll need your own Linux system • Introduction into Linux system components ◦ Installation ◦ Basic & advanced terminal commands ◦ Building applications and containers • Practical lab work submissions 3 / 14 What is Linux? ▍ https://img.devrant.com/devrant/rant/r_1578772_VbG6J.jpg | Icons by flaticon.com 4 / 14
Advantages of Linux • Runs (almost) everywhere ◦ From low-power to high performance computing • Open Source • Customizable • Free of charge 5 / 14 Components of a Linux system Component │ Example │ Description ────────────────────┼────────────────────┼──────────────────────────────── Bootloader │ grub, systemd-boot │ Starts the system Kernel │ Linux │ Interfaces with hardware Init System │ systemd / openrc │ Launches all other programs Display Server │ X11, Wayland │ Renders the graphical │ │ user interface (GUI) Display Manager │ GDM, LightDM │ Graphical login screen Desktop Environment │ Gnome, KDE, XFCE │ Defines how your GUI looks like GUI app libraries │ GTK, QT, Electron │ Allows building GUI apps with │ │ different look and feel Security Module │ SELinux, AppArmor │ Enhanced security regulation 6 / 14 What is a Linux Distribution? • Windows, MacOS, etc. only have a single OS with different Versions ◦ Windows 10, Windows 11, ... • Linux has a much greater varierty of system components ◦ Different Desktops, different init systems, different apps • A Linux Distro bundles certain components together: ◦ Different kernel versions, different desktops, different package repositories • Distros are opinionated ◦ Software selection based on certain preferences ◦ Some distros only ship open source software components (Debian, Fedora) ◦ Some distros compile everything from source (Gentoo) ◦ Different out-of-the-box security configuration (SELinux, AppArmor, Firewall frontends) ◦ Different package managers and package formats ◦ Desktop vs Server focus ◦ etc ... 7 / 14 Which Linux Distros are there? https://upload.wikimedia.org/wikipedia/commons/1/1b/Linux_Distribution_Timeline.svg A couple to point out: • Slackware is one of the oldest distros, but nowadays almost obsolete • Debian is a very stable (mostly server) distro which focuses on free software (community driven) • Ubuntu is a newcomer friendly distro based on Debian, owned by Canonical • Fedora is a community driven distro that focuses on modern software and security • ArchLinux, community driven, focuses on customization and has bleeding edge software • Gentoo is a source based distro --> software is compiled locally • NixOS is a declaratively configurable distro • RedHat and SUSE offer Enterprise Linux ◦ Alma and Rocky are community editions of RedHat Enterprise Linux (RHEL) • Kali / ParrotOS are targeted towards pentesting/security auditing (no daily-driving) • Alpine is a minimal Linux distro focusing on minimal overhead (e.g. resource-constraint hardware/containers) 8 / 14 Which Linux Distros are there? 
9 / 14 Package Managers 10 / 14 Linux filesystem explained /
├── bin -> usr/bin
├── boot
├── dev
├── etc
├── home # contains user directories
├── lib -> usr/lib
├── lib64 -> usr/lib64
├── media
├── mnt
├── opt
├── proc
├── root
├── run
├── sbin -> usr/sbin
├── srv
├── sys
├── tmp
├── usr
└── var 11 / 14
Drivers on Linux 12 / 14 How do I install my own distro? 13 / 14 Thank you for your attention! Don't forget the feedback 14 / 14