What differs between Linux distributions?

This article is a shorter version of my old one in Swedish. If you're interested in the original one, please send me a note.

• Target Group
  Designing a Linux distribution for a beginner, a office user, a gamer or a hardcore geek is very different.
• Bleeding edge
  Bleeding edge means support for the latest technology but code is less tested/used generally resulting in more bugs and security flaws.
• Packet Manager
  There is no "best packet manager", instead there are several with different pros and cons. Mainly however this is an inheritance from the "base distribution" the actual distribution is built upon (most distributions are based on one of the big distributions like Debian, Red Hat or Slackware and these in terms are built around different package management systems). Anyhow, it's a difference between distributions.
• Interface
  A graphical interface is a core component in modern operating systems. In Linux you have tons of options (just to begin with you have split Window Managing and Desktop Environment) and you can customize most to infinity more or less. One very common difference between distributions is which WM/DE they've choosed and how they've choosed to customize it.
• Hardware support
  This includes which processor architectures a distribution supports, if any specific hardware is supported, some distributions come with tons of drivers others not and so on.
• Speed, Looks or Security
  Looks (animations, effects etc.) and Security (encryption, real time watchers etc.) comes at a cost of speed. Different distributions balance this differently, some even go to the extremes like distributions with very lightwieght applications, minimal graphics etc. that provides the user with maximal speed or distributions with every possible graphics effect enabled, HD-res wallpapers etc. to give you an astonishing visual expecience. Most however try to balance this to "at least decent values all around".
• Preinstalled applications
  Office suites, choice of media players etc. is easily customizeable in Linux but different distributions choose different preinstalled sets, some even come without anything not to "get in the way" of the user.
• Looks
  Something pretty much every distribution customize. This includes background image, color scheme etc.
• Completeness
  Some distributions come with tons of applications installed and everything preconfigured while others come bare stripped so that after installation you don't even have a graphical interface. To sum it up: Some distributions try to help and guide the user to a complete set of applications while others try not to get in the way of the user, installing only what's considered necessary for it's target audience.
• Availability to low level components
  As a beginner you want the system to handle itself, new hardware are automatically detected, settings are made i GUIs etc. If you're a performance geek or just like to have complete control over your system however, you don't want the system to accidently override your tweaks or install stuff you've not choosen yourself.
• Community / Support
  This generally corresponds to the target audience and popularity of a distribution where more technical ones generally (not always) tend to have communities where you're expected to have a fundamental knowledge about Linux. If asking "too simple" questions you might be handed the RTM answer (Read The Manual). On the other hand you might have beginner forums where too technical questions might be overlooked or quickly swarmed by very basic, easy to answer, questions. Size also matters. Big communities often mean someone knows the answer to your question but it might be easier to get personal help in a less populated community. Once again, this is way to simplistic to really tell the truth, but at least you get an idea.