Why do we have different distro's, and what is the diff between Ubuntu and Fedora?

[Romanus81]

I downloaded a few .iso's to test new distributions, the three ones I've heard a lot about is Linux Mint, PCLinuxOS, and Fedora 8. There is one thing I don't get, open source software is open source, right? So why all the divergence? I heard that Ubuntu 8.04 is trying to get a smoother boot, and that Suse is developing the same thing. Why can't they both share what they are developing. So what is the difference between all these distro's? Why have so many?
I downloaded a few to try them out. I currently have Ubuntu, and have downloaded Fedora 8 and Linux mint. I have heard a lot about PCLinuxOS. So what is the difference between them?
I know Linux mint uses closed-source drivers, which I have no problem with. What makes Fedora and PCLinuxOS different? Is there some silent OS war going on to become the top linux distro? If two distro's use gnome and compiz, won't they look the same?

[MissionImpossible]

Lots of reasons, some genuinely useful and many just because almost anybody with some basic technical skills can now produce their own "distro"!

Here is a link for comparison of various distros: http://en.wikipedia.org/wiki/Compari..._distributions

FYI: The list of commercially supported distros is NOT that great!

[SunnyRabbiera]

Its due to the open nature of linux that allows so many flavors of it to sprawl, if it was closed like OSX or windows it would not have as many.
plus there are philosophical differences between certain ones, distros like mandriva, suse, linspire and xandros have a more commercial outlook while Ubuntu, debian and some others also have a commercial outlook but attain their goals by different means.
then there is codecs, some have them, some dont as having things like flash by default is controversial among users and the legality of such things are debated (though technically flash can be put on practically every distribution by default, certain laws might prevent it from being legal in some nations)

[chris4585]

Like the posts before me they make real good sense, and hit the highlights i think there's so many because thats linuxs nature, to share and develope together, distros might seem very different but sometimes they help each other and work and talk together, and plus just about anyone can built a distro these days

[VCSkier]

I came across a quote a while ago, and I think it was by Linus Torvalds. He said that choosing an operating system should by like chosing a car. I couldn't agree more.

[Steveway]

It also behaves like evolution.
Distros come up and go away, some stay and grow and get really big.
Ubuntu is one of the fishes that moved out of the water and managed to survive, it is now spreading on land and growing.
The same is with SUSE, but it's growth seemed to have slowed down.
And due to the open nature of them they can learn from each other.