With a largely successful effort made to be very compatible with programs that have been designed for MS-DOS and similar operating systems, FreeDOS includes quite a bit of software that is more updated and very often better than other common DOS versions. They also have been successful in many cases in convincing authors of software to freely release the source code for a free version of their popular software. Device drivers like CuteMouse take up less memory than alternatives.
The FreeDOS.Org address is often unresponsive. An identical page has been spotted at http://freedos.sf.net/. Files are stored at the FreeDOS site at ibiblio.
The phrase "Windows 9x" (or "Win9x") is sometimes (fairly often, actually) used to mean not only Win95, Win98, and Win98SE, but also WinMe. (This is because WinMe is the one operating system, other than Win95 and Win98(SE), that was marketed towards consumers and is still based on the same 32-bit kernel.)
These operating systems have had support officially discontinued from Microsoft. When that happened, TOOGAM spent some time collecting all the official patches from Microsoft. The archive is a bit of a mess, but TOOGAM plans to clean up the web page sometime and release the hyperlinks onto this site.
In the meantime, some of the more useful updates may appear on this site. The local directory is mswin/. The mswin/msw98be/ refers to software for "both editions" of Win98.
The operating systems using the “Windows NT” code base have generally been released in multiple “Editions”. The operating systems or editions that have the word “Server” in their name typically support more things.
Security fixes, and sometimes even new features, may come in one or more collections of files which are individually called a “service pack”. Microsoft even declared that Windows XP had reached its “end of life” before its successor, Windows Vista, was released, although “Windows XP SP2” (with “Service Pack 2”) had remained supported. Some operating system CDs will come with a service pack pre-installed. In addition to the service packs, which people make a bigger deal of, there may be a “security rollup package” (“SRP”) released.
The information on the following operating systems, such as information about available service packs, may move to separate pages hyperlinked to from this one.
There was Windows NT 3.1, Windows NT 3.5, Windows NT 3.51, and Windows NT 4.0. Later versions were released with a name other than simply “Windows NT” followed by a version number.
For Windows NT 4.0, there were a number of service packs: See Q152734/KB152734 for the latest. The download page for Windows NT 4.0 Service Pack 6a has a drop down box allowing a language to be chosen and is meant for “Windows NT 4.0” which is different than “Windows NT Server 4.0, Terminal Server Edition”. For the Server version, there is a download page for Windows NT Server 4.0, Terminal Server Edition, Service Pack 6. There are also some security rollup packages: Q299444/KB Q299444: “Post-Windows NT 4.0 Service Pack 6a Security Rollup Package (SRP)”, Window NT Server 4.0, Terminal Server Edition Security Rollup Package 1 Now Available (and it's noteworthy anchor: Patches not included in TSE SRP1) Q246009/KB246009: SP 6.0 to 6.0a upgrade.
For Service Pack 3, first review KB950717: Steps to take before you install WIndows XP Service Pack 3 for pre-requisites such as uninstalling updates. Q322389/KB322389 has a section called “Obtain the latest Windows XP service pack from the Microsoft Download Center”. For Service Pack 3, it directed to download page: Windows XP Service Pack 3 Network Installation Package for IT Professionals and Developers. That page offered a selection of languages. English Win XP SP3 (via long URL), English Win XP SP3 (via shorter URL).
There is also a download page for Win XP SP3 ISO. The ISO image is a couple hundred MB larger than the service pack by itself. English ISO of XP SP3 (via longer URL)
KB 936929: XP SP3 Release notes, download page for XP SP3 release notes