Distros 2024-10-07 Linux is a kernel. Linux-based operating systems bundle all kind of software, mostly open-source or FOSS (often coming from the GNU project), to create a friendly environment for the user. They are commonly called Linux distributions or "distros" for short. The big difference between them is in how exactly they distribute the software. We use packages and package managers for that. Debian family uses .deb packages and the "apt" package manager. RedHat family uses .rpm packages and "dnf" or "yum" as a package manager. Arch Linux uses .tar.zst packages (compressed tarballs) and the "pacman" package manager. There is a list of common operations along with a comparison of commands for major distros in the pacman/Rosetta article on ArchWiki: https://wiki.archlinux.org/title/Pacman/Rosetta There is also a small difference in what distros bundle in their installations by default. Most of the time that's not very important, since you can customize any distro to operate, look and feel exactly the way you like. From user perspective most modern distros are really very similar. The other big difference lies in your choice of a Desktop Environment (or a Window Manager), but that's a topic for a different article. One sentence description for all significant Linux distributions follows.
- Debian             -> major distribution using the .deb package format and apt package manager
  - Ubuntu           -> major family of commercial distributions by Canonical Ltd.
    - Linux Mint     -> major desktop distribution for end users, pretty beginner friendly
    - Pop! OS        -> desktop distribution shipped with System76 machines, preinstalled drivers etc.
  - LMDE             -> it's Linux Mint without Ubuntu
  - Kali Linux       -> major pentesting distribution with a lot of offensive security tools
  - Tails            -> amnesic distribution focused on privacy and anonymity with Tor deeply integrated
  - Whonix           -> virtualized distribution focused on anonymity that routes all traffic through Tor
  - Raspberry Pi OS  -> default distribution for Raspberry Pi devices
- RedHat             -> major distro family using .rpm format for package management
  - Fedora           -> testing ground for RHEL, latest and greatest, operated by the community
    - Qubes OS       -> operating system that provides security through isolation with xen virtualization
  - CentOS Stream    -> second stage of the RHEL testing ground, used to be common enterprise linux
  - RHEL             -> the industry standard enterprise linux solution
    - Alma Linux     -> compatible alternative to RHEL
    - Rocky Linux    -> another compatible alternative to RHEL
    - Oracle Linux   -> the enterprise linux solution endorsed by Oracle
  - openSUSE         -> European equivalent to RedHat which also offers enterprise options
    - SLES           -> SUSE Linux Enterprise Server
    - SLED           -> SUSE Linux Exterprise Desktop
- Arch Linux         -> community-driven, simple, lightweight, flexible, fast, power-users delight
  - Arch Linux ARM   -> Arch Linux for ARM architectures
  - Arch Linux 32    -> Arch Linux for 32-bit CPUs
  - Artix Linux      -> Arch Linux without systemd
  - Asahi Linux      -> Arch Linux on Apple silicon
  - BlackArch        -> Arch Linux with pentesting tools
  - EndeavourOS      -> Arch Linux for newbies
  - Manjaro          -> the Ubuntu of Arch Linux family
  - Parabola         -> fully FOSS and libre distribution
  - SteamOS          -> distribution exclusively for gaming with Steam, by Valve
- Slackware          -> the oldest distribution still in use, solid and reliable, but not very modern
- Gentoo             -> highly customizable source-based distribution
- NixOS              -> reproducible, declarative and reliable distribution for advanced users
- Alpine Linux       -> truly minimal, small, simple, secure, very fast, utilizing musl libc and busybox
  - postmarketOS     -> alternative operating system for mobile devices
- OpenWrt            -> small yet powerful distribution for routers, firewalls, and other embedded devices
- Android            -> major operating system for smartphones and other mobile devices
For beginners I would recommend: LMDE, Linux Mint, Fedora. Advanced users will probably have their own preference, but personally I can definitely recommend Arch Linux. On a server I would primarly use: Alpine Linux, Debian, or any of the RHEL-based distros. If you're not using GNU/Linux already, you should definitely try it!