Occupying subtle importance at the trunk of a small tree of Linux distributions and related projects is the Red Hat Package Manager (RPM). This permits each atomic module of a system, however scattered across the Unix version of a Registry, to install and un-install out of a common manifest. Other systems now use the powerful RPM installer too.

''For Windows folks, roughly it's the RedHatLinux equivalent of Control Panel>>Add/Remove Programs, though usually working much better.''

Linux old/middle-timers may recall with confusion that Debian already had a more powerful package system (AptGet) when Red Hat came out with rpm.  This begged a lot of questions about the company, and how commercial linux interests were going to interact with the ''community''.  As it stands, Debian's dpkg and apt systems are still more powerful than Red Hat's rpm system, though the features at the package format level are identical, and the Red Hat system is still simpler for neophytes.  The LinuxStandardBase also just standardized on rpm.  Presumably this was made much easier by the presence of Debian's "alien" which can install and register rpm and other packages in the deb database.

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"...it's Red Hat's equivalent of Control Panel | Add/Remove Programs, though usually working much better."

Not so. I use quite a few of the Windoze install/remove tools from M$ and other vendors. They are far, ''far'', '''''FAR''''' superior to RedHatTheCompany's install facilities. Now, granted, the only two versions of RH products I have used are 9.0 (Shrike) and FedoraCore 3, but the package managers act the same. I have noted with horror that an update requiring the download and install of 80MB of junk will fail halfway through when the package manager can't find some particular library required by some particular package. The entire rest of the install then fails. What the hey?!? Windows install packages (from ''any'' vendor) are self contained packages that install atomically and don't screw up the remainder of a complete install collection. Oy. Red Hat needs to get this mess sorted out.

''Yep, the ugly hack of just keeping redundant copies of dependancies all over the place might be a waste of  (insignificant amounts of) space/memory/bandwidth, but it makes installing so much freaking more reliable.  IMHO, having used both approaches I have to say I prefer the windoze approach, even if it does make patching a colossal PITA sometimes.''

* It seems to me that what is in the distribution package, and what gets copied into the filesystem, need not be the same thing.  Installation packages IMHO should be self-contained units, containing everything needed to operate (other than perhaps system libraries and such).  However, an intelligent package manager should be able to figure out when someone already has a component available, and not install it a second time.
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See also: AptGet