http://en.wikipedia.org/wiki/Package_management_system seems to be the most detailed explaination of package management I can find. Also there are entries discussing Linux Distributions and many of the other issues the OP would like more info on. Feel free to folow the link in my profile to my web pages. There are, I'm sure, other useful links in there too.

Somewhat on this topic, a lot of my googling has indicated that compiling your own software (usually in Slackware, but I assume it could be done on any distro) seems to offer more performance and stability - is that accurate, or am I just getting opinion mixed up with fact?

When compiling for yourself you get the option of using different compiler optimisations which may make a small performance difference, but in most cases it's going to be pretty minimal.

The other option you get is to include or exclude some features. For example, a lot of the slackware packages may come with KDE support compiled in, however, if you don't run the KDE desktop, that's not needed. You may save a small amount of memory space by not including them, but again, whether the difference would be noticable in most cases is pretty unlikely.

You could also get a distro or package that is optimized for your CPU. I know they have optimized builds of firefox (I've never used one) and Arch is optimized distro for i686. I use Arch, and there is a noticable performance over Ubuntu, though it may be due to the lightness of Arch.

So then maybe what's confusing to me, is that some people seem to report that Linux (like Windows) suffers from poor performance the more software you have *installed*, not just software that you have running... Does that make any sense? For instance, you mention "the lightness of Arch" - as a Windows user, that implies to me that you think Arch outperforms Ubuntu because it doesn't come with as much bloat right out of the box, even though in Ubuntu that bloat might not ever actually be run at all... Or am I misinterpreting that?

As for the comment about KDE, my response is similar - are you saying that because you install a lighter version of KDE, resources are saved even when it's NOT running (aside from disk space of course)?

I've used Slackware and Ubuntu for a bit, now i'm ready to try something else to see what else is out there... I'm really looking at Debian for (official) x64 support, but I also keep hearing how great Arch is...

I really recommend Arch. You only install what you need, where as Ubuntu loads a bunch of modules that arn't needed et cetera.

As for the unused software slowing down your system, that sounds very un-Linux-like. Unless your distro is starting services and loading modules, there should be no effect.

Arch does require a good deal of user setup, but the Arch wiki has a very good tutorial.

Thanks I'll certainly look into it... I really like Slackware, but I'm starting to find the x64 is really to my benefit (I use GNS3 heavily for my Cisco studies) and even though there's a port, stability is key... I like what Arch is bringing to the table, although I am still curious about Debian...

Seems like Debian's claim to fame is the # of available packages; given that I'm only really using 1 application (for now) does that help me in any way? Doesn't seem like it... But maybe I'm wrong, after all, I am posting in the 'newbie' section...

Arch actually has a lot of packages as well. One of the best thing about Arch is its build system. If you've ever used gentoo's emerge, its similar to that. There are a huge number of actively maintained packages on the AUR. With packages on the AUR, you download a PKGBUILD. You then run makepkg in the same folder as the PKGBUILD, and it automatically downloads the source, builds it and generates a package. You can then install the package with pacman. This way, its included as an installed package, and it can be easily removed, and will be recognized and not overwritten by other packages. I've used Ubuntu for several years before switching to arch, and every package I ever needed and more where in Arch.

Nope, that's not quite what I was getting at.

Sometimes when you come to build a 3rd party program, it may be that it can be built with optional support for gnome or KDE desktop environments that you can enable (usually with ./configure --enable-kde or --enable-gnome). Distros will generally include these options in their packages as they won't know which environment the user intends to use.

If you don't need this kde/gnome integration (because you don't run them), then by disabling them during the build, then it may shave a MB or so of the executable size (it won't include any of the gnome or kde specific code). This will save you a little memory when the program is running and, less significantly, a little diskspace too. It will also mean that the system takes less time to load that program into memory when its first run because it has less to read from the disk. The gains are pretty minimal and it's not something you'd really worry too much about, unless you're running on a memory constrained system, in which case every little bit helps.

I've been running Slackware a very long time now, somewhere in the region of 13 years. I tried Ubuntu out of curiosity a while back, but I just couldn't get on with it. Though I'm obviously a confirmed Slacker, I'll admit that I've had an urge to give Arch a try for a while now. I really should give it some attention sooner or later and see what I think to it.

Well if you have Mysql installed, and apache2 and whatever else and aren't using them then your system will probably startup and run slower than a system that does not have those 'services' running. I'm referring to packages that hactually have daemons running, because just a large number of files that do nothing shouldn't be a perfomance hit. It's when you have to wait for them to startup, or look at the additional memory they consume, or processor time.

Some Distros seem to install a lot more junk that runs by default than others do. Debian which you mentioned is more on the lean side than say Ubuntu. Heck you can install a Debian base system then install only what you want on top of that to have a very lean system when you are done. The Debian base sytem is so minimalistic the last time I installed it, it didn't even have a ssh server running, now THAT is lean..

Compare that to a distro that has network discovery services running like Bonjour, or the appletalk protocol netatalk, bittorent or HPLIP services running automatically. I don't have an HP printer, why is HPLIP even installed ? I don't have any old macs on my network why do I have the appletalk service ? Why do I need bonjour to automatically discover apple / multimedia devices on the network ? When installing any Linux distro it's a good idea to look at the services that were installed and are running by default. You may find several you can remove, and quite frankly I don't think they should have been there to begin with. If I need those services I will install them myself thank you very much.

Part of the price of making a distro user/newbie friendly is installing all sorts of junk by default so things 'just work', performance is usually the penalty you pay.

So with those responses in mind, it leads me back to the same question every newbie has about Linux - WHY so many distributions, and what's REALLY the difference? Based on my experience, and what we're talking about here, it really just seems like pre-installed software across the board...

Each distro has its own targed user group. Some are targeted for lightweight (Arch) some are targeted for servers (CentOS, RedHat) some are for everyday users (Ubuntu) and some are supposed to be customizable (Arch, Slackware). The differences vary from how much configurations the user has to do (Ubuntu has almost none, Arch is almost 100% user) to which packages are install (Arch comes with the base packages and Ubuntu has a full working Desktop manager). If your a linux noob then your best bet is to use Ubuntu until you get comfortable with linux, and then maybe switch to something more lightweight.

"Because somebody wanted to make them.", I guess.

You totally forgot Debian for Stability..

Of course Stability comes at a price too, that price currently being around 18 Months between releases of each stable version. 18 Months is a LONG time in computing and the programs on Debian tend to get 'stale' since the versions are not updated during that 18 months. Only security patches are applied to the system. Debian also requires a bit more manual configuration to get some things working.

Along comes some guy and takes a snapshot of the Debian Unstable repository (two steps away from Debians Stable distribution) modifies that unstable code They modify the install so it puts in their predetermined list of packages, slap on a coat of brown paint, preconfigure a few things to make it easier for newbies, and they call it Ubuntu, the greatest thing since sliced bread !! And a new Distro is born. Then repeats this pretty much every 6 months. I'm not sure if they do a fresh snapshot each time or sync their own dev servers from the unstable repositories..

So do you want a distro that updates every 6 months so you are current but the system tends to be a little slower and kinda flaky at times, or do you want a Distro you can install and be good for 2 Years with minimal issues and only worry about minor security updates.. THAT is the difference between Debian and Ubuntu which is based on Debian. Many people don't want to chase the upgrade train, they don't care about having the latest and greates they just want a stable system that performs well and just works. Don't get me wrong Ubuntu gives back to Debian as well, I have nothing against them, it's just not my cup of tea. I'll run Debian testing or unstable when I feel like living on the edge..

the terms become Far more relevant the more you get into a distro and develop a linux pallet if i should say. after you have tasted the different types... usually people find one that suits them most and they stick with it. after working with slackware for a while you will generally be able to tell what a distro is like if they describe it as "slackware-based" or "debian-based"