Debian-based, Ubuntu-based...What do these mean?

[Jucato]

Ubuntu is Debian-based. Knoppix recently changed to become Ubuntu-based. PCLinuxOS is Mandrake/Mandriva-based, etc.

What does it mean for a distro to be based on another distro?
What does it mean for a developer/maintainer and for an end-user? :-k

[Ubuntuud]

Ubuntu is debian based. They took debian and modded it to what they had in mind (maybe modded sounds not very respectful).

[prizrak]

"modded" sounds like they threw a turbo on that biatch and a huge wing on the back. So Ubuntu is a riced out Debian?

[Sef]

What does it mean for a developer/maintainer and for an end-user?

For an end user, it means that if you use a distro based on debian, you'll know about .deb, apt-get, and dpkg. Thus if you switch between debian based distros, you don't have to totally relearn how to do things. You will have an idea already.

[Rhapsody]

With all these distros based on another distro, I started thinking. Lots of distros are based on another distro, but now MEPIS is going to be Ubuntu-based, and Ubuntu is already Debian-based, which adds second layer. Since most distros are released under entirely free and open source licences, this could theoretically continue into infinity. So which distro actually holds the record for the most layers in this?

[Jucato]

The case of SimplyMEPIS is also what got me thinking.
If being *-based just means that you just mod what you're based on, then how will that apply to MEPIS, which was, if I remember correctly, KNOPPIX based before. And KNOPPIX is Debian-based (AFAIK)...

What does it mean for packages/repositories? It's starting to get confusing, if you try thinking about it. Maybe I just think to much... :D