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From kernel all the way up to the Desktop Environment, where does Ubuntu reside?

  1. Linux kernel is the kernel for all distros.

  2. The basic utilities (fdisk, ls, bash, whiptail, etc.) are mostly GNU tools and (almost) compatible to almost-all Unix-like variants.

  3. The systems of (userspace-resident) device drivers, pamd, udev, upower, etc. are also conformant to kernel APIs and ABIs interfaces.

  4. The X system is also not Ubuntu.

  5. The desktop environment (Gnome, Kde, etc.) is also not Ubuntu.

So, where is Ubuntu? In particular, where is Ubuntu's source code?

marked as duplicate by Kulfy, mook765, pomsky, Rinzwind, Warren Hill May 28 at 6:51

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  • 2
    Package Management and support. apt uses Ubuntu's repositories to retrieve packages. These packages are generally managed by Ubuntu according to distribution, dependency and lifecycle of the release. If you change sources.list your OS will break horribly. I once tried replacing Ubuntu's sources with Kali's sources and then everything broke up. I needed to install the OS again. – Kulfy May 28 at 6:15
  • @Kulfy: That is due to the trigger scripts that are run in the post-processing phase of an apt/yum/pacman command. Mainly, where a particular config file is put is distro-dependent. – T. D. Nguyen May 28 at 7:38

Ubuntu is not a single component of the system, it is a Linux distribution (aka distro).

This basically means a particular way of packaging all the components together. That includes selecting the right software (libraries, applications) to be able to work together seamlessly, choosing their right versions and provide patches where they’re needed (typically kernel).

This is practically achieved by providing install images and package repositories.

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    So, in short, a distro makes final decision between choices unspecified by standards, interfaces. – T. D. Nguyen May 28 at 7:46

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