Windows 95 introduced numerous functions and features that were featured in later Windows versions, and continue in modern variations to this day, such as thetaskbar,notification area, and the "Start" button which summons theStart menu.[1][4] Accompanied by an extensive marketing campaign[1] that generated much prereleasehype,[5] it was a major success[6] and is considered to be one of the biggest and most important products in the personal computing industry.[7][8] Three years after its introduction, Windows95 was followed byWindows98. Microsoft ended mainstream support for Windows95 on December 31, 2000. LikeWindowsNT3.51, which was released shortly before, Windows95 received only one year of extended support, ending on December 31, 2001.
The initial design and planning of Windows 95 can be traced back to around March 1992,[9][10][11] just around the time before the release ofWindows 3.1. At this time,Windows for Workgroups 3.11 andWindows NT 3.1 were still in development. At this point, Microsoft's strategy was to have a next generation, high-end OS based on Windows NT, namely,Cairo, and a low-end, consumer-focused one as an evolution of Windows 3.1. The latter strategy was to develop a 32-bit underlying kernel and filesystem with 32-bit protected mode device drivers in Windows for Workgroups 3.11, to be used as the basis for the next version of Windows, code named "Chicago." Cairo would be Microsoft's next-generation operating system based on Windows NT, featuring a new user interface and an object-based file system, but it was not planned to be shipped before 1994. Cairo would never be shipped, however, although elements from the Cairo project eventually shipped in Windows NT 4.0 in late July 1996, without the object-based file system, which would later evolve intoWinFS.
Simultaneously with Windows 3.1's release,IBM started shippingOS/2 2.0. Microsoft realized they required an updated version of Windows that could support 32-bit applications and preemptive multitasking, but could still run on low-end hardware (Windows NT did not). Initially, the "Chicago" team did not know how the product would be packaged. Initial thoughts were there might be two products, MS-DOS 7, which would just be the underlying OS, an evolution of the Windows for Workgroups 3.11 kernel, with a character mode OS on top, and a fully integrated graphical Windows OS. But soon into the project, the idea of MS-DOS 7 was abandoned and the decision was made to develop only an integrated graphical OS Windows "Chicago."
Before Windows 95's official release, users in theUnited States andUnited Kingdom had an opportunity to participate in the Windows 95 Preview Program.[12] For US$19.95/£19.95, users would receive several 3.5-inch floppy disks that would be used to install Windows 95 either as an upgrade from Windows 3.1 or as a fresh installation. Participants were also given a free preview ofThe Microsoft Network (MSN), theonline service that Microsoft launched with Windows 95. During the preview period, Microsoft established various electronic distribution points for promotional and technical documentation on Chicago,[13] including a detailed document for media reviewers describing the new system highlights.[13][14] The preview versions expired in November 1995, after which the user would have to purchase their copy of the final version of Windows 95.
Windows 95 was designed to be maximally compatible with existingMS-DOS and 16-bit Windows programs anddevice drivers while offering a more stable and better performing system.[15][16] The Windows 95 architecture is an evolution ofWindows for Workgroups' 386 enhanced mode.
Configuration Manager (CONFIGMG)
Responsible for implementingPlug and Play functionality; monitoring hardware configuration changes; detecting devices usingbus enumerators; and allocatingI/O ports,IRQs,DMA channels andmemory in a conflict-free fashion.[17]
Installable File System Manager (Input/Output Subsystem)
Access requests to physical media are sent toInput/Output Supervisor, a component responsible for scheduling the requests. Each physical media has its device driver: access to the disk is performed by aport driver, while access to aSCSI device is handled by aminiport driver working atop the SCSI layer. Port and Miniport drivers perform I/O operations in 32-bit protected mode, bypassing MS-DOS andBIOS, significantly improving performance. In case there is no native Windows driver for a certain storage device, or if a device is forced to run in compatibility mode, theReal Mode Mapper can access it through MS-DOS.[19]
32-bit Windows programs are assigned protected memory segments, which can be adjusted to any desired size, and memory areas outside the segment cannot be accessed by a program, that limited harm to other programs and the system when a program crashed. Before this, programs used fixed non-exclusive 64 KB segments. While the 64 KB size was a serious handicap in DOS and Windows 3.x, lack of guarantee of exclusiveness was the cause of stability issues because programs sometimes overwrote each other's segments, a crashing Windows 3.x program could knock out surrounding processes.[citation needed] Unfortunately for compatibility reasons some parts of the 32-bit Windows program memory was non-exclusive and shared among the whole system (most famously the first 1MiB of the address space),[20] this meant that in Windows 95 a crash which incorrectly modified this shared memory could still cause harm to other programs or the system (full memory protection only came to consumer Windows systems with the launch of Windows XP).
TheWin32 API is implemented by three modules, each consisting of a 16-bit and a 32-bit component:
To end-users, MS-DOS appears as an underlying component of Windows 95. For example, it is possible to prevent the loading of the graphical user interface and boot the system into a real-mode MS-DOS environment. This was done by insertingcommand.com into the autoexec.bat file or changing the BootGUI variable in the MSDOS.SYS file to 0. This sparked debate amongst users and professionals regarding the extent to which Windows 95 is an operating system or merely a graphical shell running on top of MS-DOS.[19][21][22]
When the graphical user interface is started, the virtual machine manager takes over the filesystem-related and disk-related functionality. MS-DOS itself is demoted to a compatibility layer for 16-bit device drivers.[19] This contrasts with earlier versions of Windows which rely on MS-DOS to perform file and disk access (Windows for Workgroups 3.11 could also largely bypass MS-DOS when32-bit file access and32-bit disk access were enabled). Keeping MS-DOS in memory allows Windows 95 to use DOS device drivers when suitable Windows drivers are unavailable. Windows 95 is capable of using all 16-bit Windows 3.x drivers.
Unlike Windows 3.x, DOS programs running in Windows 95 do not need DOS drivers for the mouse, CD-ROM and sound card; Windows drivers are used instead.HIMEM.SYS is still required to boot Windows 95.EMM386 and other memory managers, however, are only used by DOS programs. In addition,CONFIG.SYS andAUTOEXEC.BAT settings (aside from HIMEM.SYS) do not affect Windows programs. DOS games, which could not be executed on Windows 3.x, can run inside Windows 95 (games tended to lock up Windows 3.x or cause other problems). As with Windows 3.x, DOS programs that useEGA orVGA graphics modes run in windowed mode (CGA andtext mode programs can continue to run).[19]
On startup, the MS-DOS component in Windows 95 responds to a pressedF8 key by temporarily pausing the default boot process and presenting the DOS boot options menu, allowing the user to continue starting Windows normally, start Windows insafe mode or exit to the DOS prompt.[21] As in previous versions ofMS-DOS, there is no 32-bit support and DOS drivers must be loaded for mice and other hardware.
As a consequence of DOS compatibility, Windows 95 has to keep internal DOS data structures synchronized with those of Windows 95. When starting a program, even a native 32-bit Windows program, MS-DOS momentarily executes to create a data structure known as theProgram Segment Prefix. It is even possible for MS-DOS to run out ofconventional memory while doing so, preventing the program from launching.[21] Windows 3.x allocatedfixed segments in conventional memory first. Since the segments were allocated as fixed, Windows could not move them, which would prevent any more programs from launching.
Microsoft partially removed support forFile Control Blocks (an API hold-over of DOS 1.x andCP/M) in Windows 95 OSR2 (OEM Service Release 2). FCB functions can readFAT32 volumes, but not write to them.
With merging Windows together with MS-DOS, Microsoft had effectivelylocked-in users who may have been using a different non-Microsoft DOS, likePC DOS andDR DOS, who could previously make use of Windows 3.x without requiring Microsoft's MS-DOS.Caldera demostrated that Windows 95 could in fact run on top of its DR DOS operating system, and argued that Microsoft was being anti-competitive, which would prove useful in a latercourt case between Caldera and Microsoft.[23][24]
Windows 95 introduced a redesignedshell based around adesktop metaphor;File shortcuts (also known as shell links) were introduced[25] and the desktop was re-purposed to hold shortcuts to applications, files and folders, reminiscent ofMac OS.
InWindows 3.1, the desktop was used to display icons of running applications. In Windows 95, the currently running applications were displayed as buttons on ataskbar across the bottom of the screen.[26] The taskbar also contained a notification area used to display icons for background applications, a volume control and the current time.[27]
TheStart menu, invoked by clicking the "Start" button on the taskbar or by pressing theWindows key, was introduced as an additional means of launching applications or opening documents. While maintaining the program groups used by its predecessorProgram Manager, it also displayed applications within cascading sub-menus.[28]
The previousFile Manager program was replaced byWindows Explorer and the Explorer-basedControl Panel and several otherspecial folders were added such as My Computer, Dial-Up Networking, Recycle Bin, Network Neighborhood, My Documents, Recent documents, Fonts, Printers, andMy Briefcase among others.AutoRun was introduced for CD drives.
The user interface looked dramatically different from prior versions of Windows, but its design language did not have a special name likeMetro,Aqua orMaterial Design. Internally it was called "the new shell" and later simply "the shell".[29] The subproject within Microsoft to develop the new shell was internally known as "Stimpy".[30]
In 1994, Microsoft designersMark Malamud and Erik Gavriluk approachedBrian Eno to compose music for the Windows 95 project.[31] The result was the six-second start-up music-sound of the Windows 95 operating system,The Microsoft Sound and it was first released as a startup sound in May 1995 on Windows 95 May Test Release build 468.[32] The previous "tada" startup sound from Windows 3.1 became the shutdown sound for Windows 95.
When released for Windows 95 and Windows NT 4.0,Internet Explorer 4 came with an optionalWindows Desktop Update, which modified the shell to provide several additional updates to Windows Explorer, including aQuick Launch toolbar, and new features integrated with Internet Explorer, such asActive Desktop (which allowed Internet content to be displayed directly on the desktop).
Some of the user interface elements introduced in Windows 95, such as the desktop, taskbar, Start menu and Windows Explorer file manager, remained fundamentally unchanged on future versions of Windows.
Windows 95 included support for 255-character mixed-caselong filenames[33] andpreemptively multitasked protected-mode 32-bit applications. 16-bit processes were still co-operatively multitasked.
Windows 95 tried to automate device detection and configuration as much as possible, but could still fall back to manual settings if necessary. During the initial install process of Windows 95, it would attempt to automatically detect all devices installed in the system.
Windows 95 also introduced the Device Manager to indicate which devices were working optimally with correct drivers and configuration and to allow the user to override automatic Plug and Play-based driver installation with manual options or give a choice of several semi-automatic configurations to try to free up resources for devices that still needed manual configuration.
32-bit File Access is necessary for thelong file names feature introduced with Windows 95 through the use of theVFAT file system extension. It is available to both Windows programs and MS-DOS programs started from Windows (they have to be adapted slightly, since accessing long file names requires using largerpathnamebuffers and hence differentsystem calls). Competing DOS-compatible operating systems released before Windows 95 cannot see these names. Using older versions of DOS utilities to manipulate files means that the long names are not visible and are lost if files are moved or renamed and by the copy (but not the original) if the file is copied. During a Windows 95 automatic upgrade of an older Windows 3.1 system, DOS and third-party disk utilities which can destroy long file names are identified and made unavailable. When Windows 95 is started in DOS mode, e.g. for running DOS programs, low-level access to disks is locked out. In case the need arises to depend on disk utilities that do not recognize long file names, such as the MS-DOS 6.x's defrag utility, a program called LFNBACK for backup and restoration of long file names is provided on the CD-ROM, specifically in its \ADMIN\APPTOOLS\LFNBACK directory.[citation needed]
Windows 95 followedWindows for Workgroups 3.11 with its lack of support for older, 16-bitx86 processors, thus requiring anIntel 80386 (or compatible). While the OS kernel is 32-bit, much code (especially for the user interface) remained 16-bit for performance reasons as well as development time constraints.
The introduction of32-bit file access in Windows for Workgroups 3.11 meant that 16-bit real mode MS-DOS is not used for managing the files while Windows is running, and the earlier introduction of the32-bit disk access means that the PCBIOS is often no longer used for managing hard disks. DOS can be used for running old-styledrivers for compatibility, but Microsoft discourages using them, as this prevents proper multitasking and impairs system stability.Control Panel allows a user to see which MS-DOS components are used by the system; optimal performance is achieved when they are bypassed. The Windowskernel uses MS-DOS style real-mode drivers inSafe Mode, which exists to allow a user to fix problems relating to loading native, protected-mode drivers.
Official system requirements were anIntel 386DX CPU of any speed, 4 MB of system RAM and 50–55 MB of hard disk space depending on features selected. These minimal claims were made in order to maximize the available market of Windows 3.1 migrations. This configuration would rely heavily onvirtual memory and was only optimal for productive use on single-tasking dedicated workstations.[34] It was possible to run Windows 95 on a 386 SX, but this led to even less acceptable performance due to its 16-bit external data bus. To achieve optimal performance, Microsoft recommended ani486 or compatible CPU with at least 8 MB of RAM.[35]
Windows 95 may fail to boot on computers with a processor faster than 2.1 GHz and more than approximately 480 MB of memory.[36][37][38] In such a case, reducing the file cache size or the size of video memory can help.[36] The theoretical maximum according to Microsoft is 2 GB.[39]
Most copies of Windows 95 were onCD-ROM, but a3+1⁄2-inch floppy version was also available for older machines. The retail floppy disk version of Windows 95 came on 13DMF formatted floppy disks, while OSR2.1 doubled the floppy count to 26. Both versions exclude additional software that the CD-ROM version might have featured.Microsoft Plus! for Windows 95 was also available on floppy disks.
Windows 95 was superseded byWindows 98, which also included theWindows Desktop Update andInternet Explorer 4 by default. It could still be directly upgraded by either Windows 2000 Professional[40] orWindows Me.Office 2000 was the last version ofMicrosoft Office to be compatible with Windows 95. Similarly,Windows Media Player 7.0, released in June 2000, andDirectX 8.0a, released in February 2001, are the last versions of Windows Media Player and DirectX available for Windows 95, respectively.
Updates for Windows 95 could be installed via theWindows Update website. The Windows Update website for Windows 95 and 98 was removed in 2011.[41] An independent project named Windows Update Restored aims to restore the Windows Update websites for older versions of Windows, including Windows 95.[42][41]
Windows 95 originally shipped withoutInternet Explorer, and the default network installation did not includeTCP/IP, the network protocol used on the Internet. At the release date of Windows 95, Internet Explorer 1.0 was available,[45] but only in thePlus! add-on pack for Windows 95, which was a separate product. The Plus! pack did not reach as many retail consumers as the operating system itself (it was mainly advertised for its non-Internet-related add-ons such asthemes and better disk compression) but was usually included inpre-installed (OEM) sales, and at the time of Windows 95's release, the web was being browsed mainly with a variety of early web browsers such asNCSA Mosaic andNetscape Navigator (promoted by products such asIBox).
Windows 95 OEM Service Release 1 was the first release of Windows to includeInternet Explorer (version2.0) with the OS. While there was no uninstaller, it could be deleted easily if desired. OEM Service Release 2 includedInternet Explorer 3. The installation ofInternet Explorer 4 on Windows 95 (or the OSR2.5 version preinstalled on a computer) gave Windows 95 Active Desktop and browser integration into Windows Explorer, known as theWindows Desktop Update. The CD version of the last release of Windows 95, OEM Service Release 2.5 (version 4.00.950C), includes Internet Explorer 4, and installs it after Windows 95's initial setup and first boot are complete.
While only the 4.x series of the browser contained the option to install the Windows Desktop Update features, the subsequent 5.x version had the option hidden. Editing the installer's configuration file located in a temporary folder would make the feature available in the installer. Alternatively, Windows 95 and Windows NT 4.0 users could first install IE 4 with the desktop update before installing a newer version of Internet Explorer. The last version of Internet Explorer supported on Windows 95 isInternet Explorer 5.5 with SP2, which was released on July 23, 2001. Windows 95 shipped with Microsoft's dial-up online service calledThe Microsoft Network (MSN).
Sales were projected as high as $720 million on release day. The marketing campaign for Windows 95 was estimated at $1 billion and spanned the entire industry.[46] The Windows 95 release included a commercial featuringThe Rolling Stones' 1981 single "Start Me Up" (a reference to the Start button).[47] It was widely reported thatMicrosoft paid the Rolling Stones between US$8 and US$14 million for the use of the song in the Windows 95 advertising campaign. However, Microsoft said that this was just a rumour spread by the band to increase their market value, and the company paid US$3 million.[48] A 30-minute promotional video, labeled a "cyber sitcom," featuringJennifer Aniston andMatthew Perry, was also released to showcase the features of Windows 95.[49] Microsoft's US$200 million advertising campaign featured stories of people waiting in line outside stores to get a copy.[50]
In the UK, the largest computer chain,PC World, received a large quantity of point-of-sale material; many branches opened at midnight to sell the first copies of the product. Copies ofThe Times were available for free, and Microsoft paid for 1.5 million issues (twice the daily circulation at the time).[51]
The release included a number of "Fun Stuff" items on the CD, including music videos ofEdie Brickell's "Good Times"[53] andWeezer's "Buddy Holly," a trailer for the 1995 filmRob Roy and the computer gameHover![54]
Sales were strong, with one million copies shipped worldwide in just four days.[55] According toInternational Data Corporation, by the end of 1998, Windows 95 was the most used desktop OS with 57.4% of the marketshare, with its successorWindows 98 coming in second at 17.2%. Windows 95 also still sold more non-OEM copies to large customers in the month of May 1999, which analysts attributed to large companies opting to wait for the release ofWindows 2000.[56]
"OSR2" redirects here. For the gene, seeOSR2 (gene).
Several Windows 95 editions have been released. Only the original release was sold as a shrink-wrapped product; later editions were provided only to computerOEMs for installation on new PCs. For this reason, these editions are known asOEM Service Releases (OSR).
Together with the introduction of Windows 95, Microsoft released theMicrosoft Plus! for Windows 95 pack, which contained several optional components for high-end multimedia PCs, including Internet Explorer, DriveSpace and additional themes.
The first service pack was made available half a year after the original release and fixed several small bugs.[57]
The second service pack mainly introduced support for new hardware, most notably support for hard drives larger than 2 GB in the form of theFAT32 file system.[58] This release was never made available to end-users directly and was only sold through OEMs (OSR2) with the purchase of a new PC.
A full third service pack was never released, but two smaller revisions to the second were released in the form of a USB Supplement (OSR2.1) and theWindows Desktop Update (OSR2.5).[59] Both were made available as updated disc images shipped by OEMs, and the Windows Desktop Update was also released with the standalone Internet Explorer 4.0 release. OSR2.5 was notable for featuring several changes to the Windows Explorer, integrating it with Internet Explorer 4.0—this version of Internet Explorer looks very similar to the one featured in Windows 98.
^At least when running only 32-bit protected mode applications
^The version string displayed in the "System properties" tab. Right-click on "My Computer" and choose "Properties".
^The version of updated system files. Note that most system files which have not been updated often retain their old version number. Version numbers are not consistently used: some system files may have older or newer build numbers or use a version numbering scheme separate from regular system files.
^abThe Microsoft Knowledge Base reports 4.03.1214. This USB Supplement to OSR2 (included with OSR2.5 only, namedusbupd2.exe) contains an updated VMM.VXD with support for the Pentium Pro and Pentium II. This file has version 4.03.1216 and has a timestamp of September 23, 1997 09:51:18.
On December 31, 2001, Microsoft ended its support for Windows 95, making it an "obsolete" product per the Microsoft Lifecycle Policy.[75]
Many features have since become key components of the Microsoft Windows series, such as theStart menu and thetaskbar, originated in Windows 95. Neil MacDonald, aGartner analyst, said that Windows 95 "was a quantum leap in difference in technological capability and stability." Ina Fried ofCNET said that "by the time Windows 95 was finally ushered off the market in 2001, it had become a fixture on computer desktops around the world."[51]
The basic design of Windows 95, with its combination of a desktop that can be used as a storage location, a pop-out application menu, and a taskbar showing running applications, a clock and asystem tray, was strongly influential on future user interfaces for desktop operating systems. The core UI concepts of Windows 95 have persisted up to the present day in both Windows itself as well as on other operating systems likeLinux, with the default behaviour of desktop environments likeKDE andXFCE replicating it in many aspects.[76]
Even though support for Windows 95 has ended, the software has occasionally remained in use on legacy systems for various purposes. In addition, some video game enthusiasts choose to use Windows 95 for theirlegacy system to play old DOS games, although some other versions of Windows such as Windows 98 can also be used for this purpose.
^Romano, Mike (September 17, 1998) [1998-09-16]."The mouse that roared. Forget the feds. It's up to an obscure Utah company to prove what we already know: that Microsoft is a monopoly".Seattle Weekly. Archived fromthe original on June 24, 2017. RetrievedJune 24, 2017.Furthermore, Caldera claims that Microsoft's flagship product, Windows 95, is nothing more than an "artificial tie" between its MS-DOS operating system andWindows graphic interface with no business justification other than to keep competing underlying operating systems—like Caldera's DR-DOS—off the market. To prove its point, Caldera will soon release a piece of demonstration software called "WinBolt," which, it says, will allow users to install the Windows 95 interface atop DR-DOS. The demo will show, Caldera says, that there is no significant technological advancement, or justified business efficiency, to the combination of MS-DOS with Windows in Windows 95.[1]
^"Windows '95 sales at $720m".Meriden Record-Journal. Bloomberg Business News. August 26, 1995. p. 25.
^Microsoft detractors were quick to point out that the second verse of "Start Me Up" begins "you make a grown man cry" (a line which is repeated throughout). The phrase subsequently featured as a humorous reference in many critical expositions of Windows 95.
