   #copyright

Microsoft Windows

2007 Schools Wikipedia Selection. Related subjects: Software

   CAPTION: Microsoft Windows

   Windows logo
   Screenshot of Windows Vista, the newest release of Microsoft Windows.
   Company/ developer: Microsoft Corporation
   OS family: MS-DOS-based, Windows NT, Windows 9x, Windows CE
   Source model: Closed source
   Stable release: Windows Vista
   NT 6.0  ( November 8, 2006) [[ +/-]]
   Preview release: Windows Server "Longhorn"
   August 2006 CTP
   NT 6.0.5600  ( September 12, 2006) [[ +/-]]

   License: MS- EULA
   Working state: Current
   Website: Microsoft Windows

   Microsoft Windows is a family of operating systems by Microsoft. They
   can run on several types of platforms such as servers, embedded devices
   and, most typically, on personal computers. Microsoft first introduced
   an operating environment named Windows in November 1985 as an add-on to
   MS-DOS in response to the growing trend of graphical user interfaces
   (GUI) popularized by the Macintosh. Microsoft Windows eventually came
   to dominate the world's personal computer market. At the 2004 IDC
   Directions conference, IDC Vice President Avneesh Saxena stated that
   Windows had approximately 90% of the client operating system market.

Versions

   The term Windows collectively describes any or all of several
   generations of Microsoft (MS) operating system (OS) products. These
   products are generally categorized as follows:

16-bit operating environments

   The early versions of Windows were often thought of as just graphical
   user interfaces or desktops, mostly because they were started from
   MS-DOS and used it for file system services. However even the earliest
   16-bit Windows versions already assumed many typical operating system
   functions, notably having their own executable file format and
   providing their own device drivers (timer, graphics, printer, mouse,
   keyboard and sound) for applications. Unlike MS-DOS, Windows allowed
   users to execute multiple graphical applications at the same time,
   through cooperative multitasking. Finally, Windows implemented an
   elaborate, segment-based, software virtual memory scheme which allowed
   it to run applications larger than available memory: code segments and
   resources were swapped in and thrown away when memory became scarce,
   and data segments moved in memory when a given application had
   relinquished processor control, typically waiting for user input.
   Examples include Windows 1.0 (1985) and Windows 2.0 (1987) and its
   close relative Windows/286.

Hybrid 16/32-bit operating environments

   Windows/386 introduced a 32-bit protected mode kernel and virtual
   machine monitor. For the duration of a Windows session, it created one
   or more virtual 8086 environments and provided device virtualization
   for the video card, keyboard, mouse, timer and interrupt controller
   inside each of them. The user-visible consequence was that it became
   possible to preemptively multitask multiple MS-DOS environments in
   separate windows (graphical applications required switching the window
   to full screen mode). Windows applications were still multi-tasked
   cooperatively inside one of such real-mode environments.

   Windows 3.0 (1990) and Windows 3.1 (1992) improved the design, mostly
   thanks to virtual memory and loadable virtual device drivers ( VxDs)
   which allowed them to share arbitrary devices between multitasked DOS
   windows. Because of this, Windows applications could now run in 16-bit
   protected mode (when Windows was running in Standard or 386 Enhanced
   Mode), which gave them access to several megabytes of memory and
   removed the obligation to participate in the software virtual memory
   scheme. They still ran inside the same address space, where the
   segmented memory provided a degree of protection, and multi-tasked
   cooperatively. For Windows 3.0, Microsoft also rewrote critical
   operations from C into assembly, making this release faster and less
   memory-hungry than its predecessors.

Hybrid 16/32-bit operating systems

   With the introduction of 32-bit File Access in Windows for Workgroups
   3.11, Windows could finally stop relying on DOS for file management.
   Leveraging this, Windows 95 introduced Long File Names, reducing the
   8.3 DOS to the role of a boot loader. MS-DOS was now bundled with
   Windows; this notably made it (partially) aware of long file names when
   its utilities were run from within Windows, but angered the
   competition. The most important novelty was the possibility of running
   32-bit multi-threaded preemptively multitasked graphical programs.
   However, the necessity of keeping compatibility with 16-bit programs
   meant the GUI components were still 16-bit only and not fully
   reentrant, which resulted in reduced performance and stability.

   There were three releases of Windows 95 (the first in 1995, then
   subsequent bug-fix versions in 1996 and 1997, only released to OEMs,
   which added extra features such as FAT32 support). Microsoft's next OS
   was Windows 98; there were two versions of this (the first in 1998 and
   the second, named "Windows 98 Second Edition", in 1999). In 2000,
   Microsoft released Windows Me (Me standing for Millennium Edition),
   which used the same core as Windows 98 but adopted the visual
   appearance of Windows 2000, as well as a new feature called System
   Restore, allowing the user to set the computer's settings back to an
   earlier date. It was not a very well received implementation, and many
   user problems occurred. Windows Me was considered a stopgap to the day
   both product lines would be seamlessly merged. Microsoft left little
   time for Windows Me to become popular before announcing their next
   version of Windows which would be called Windows XP.

32-bit operating systems

   This family of Windows systems was designed and marketed for
   higher-reliability business use, and was unencumbered by any Microsoft
   DOS heritage. The first release was Windows NT 3.1 (1993, numbered
   "3.1" to match the Windows version and to one-up OS/2 2.1, IBM's
   flagship OS codeveloped by Microsoft and Windows NT's main competitor
   at the time), which was followed by NT 3.5 (1994), NT 3.51 (1995), and
   NT 4.0 (1996); the latter implemented the Windows 95 user interface.
   Microsoft then moved to combine their consumer and business operating
   systems. Their first attempt, Windows 2000, failed to meet their goals,
   and was released as a business system. The home consumer edition of
   Windows 2000, codenamed " Windows Neptune", ceased development and
   Microsoft released Windows Me in its place. Eventually "Neptune" was
   merged into their new project, Whistler, which later became Windows XP.
   Since then, a new business system, Windows Server 2003, has expanded
   the top end of the range, and the forthcoming Windows Vista will
   complete it. Windows CE, Microsoft's offering in the mobile and
   embedded markets, is also a true 32-bit operating system.

64-bit operating systems

   Windows NT included support for several different platforms before the
   x86-based personal computer became dominant in the professional world.
   Versions of NT from 3.1 to 4.0 supported DEC Alpha and MIPS R4000,
   which were 64-bit processors, although the operating system treated
   them as 32-bit processors.

   With the introduction of the IA-64 ( Itanium) architecture, and later
   the AMD64/ EM64T (or x64 in Microsoft terminology) architectures,
   Microsoft released new versions of its more contemporary operating
   systems to support them. The modern 64-bit Windows family comprises
   Windows XP 64-bit Edition for IA-64 systems, Windows XP Professional
   x64 Edition for AMD64/EM64T systems, and Windows Server 2003, in both
   IA-64 and x64 editions. The x64 versions of Windows XP Professional and
   Server 2003 were released on April 25, 2005, while the IA-64 versions
   were released at the same time as their mainstream x86 (32-bit)
   counterparts. Windows Vista will be the first end-user version of
   Windows that Microsoft plans to release simultaneously in 32-bit and
   x64 editions.

History

   Microsoft has taken two parallel routes in operating systems. One route
   has been the home user and the other has been the professional IT user.
   The dual route has generally led to the home versions with more "eye
   candy" and less functionality in networking and security, and
   professional versions with less "eye candy" and better networking and
   security.

   The first independent version of Microsoft Windows, version 1.0,
   released in November 1985, lacked a degree of functionality and
   achieved little popularity. Windows 1.0 did not provide a complete
   operating system; rather, it extended MS-DOS. Microsoft Windows version
   2.0 was released in November, 1987 and was slightly more popular than
   its predecessor. Windows 2.03 (release date January 1988) had changed
   the OS from tiled windows to overlapping windows. The result of this
   change led to Apple Computer filing a suit against Microsoft alleging
   infringement on Apple's copyrights.

   Microsoft Windows version 3.0, released in 1990, was the first
   Microsoft Windows version to achieve broad commercial success, selling
   2 million copies in the first six months. It featured improvements to
   the user interface and to multitasking capabilities. In August 1995,
   Microsoft released Windows 95, which made further changes to the user
   interface and was the first Windows version to utilize multitasking.

   In July 1993, Microsoft released Windows NT based on a new kernel. NT
   was considered to be the professional OS. NT and the Windows
   non-professional line would later be fused together to create Windows
   XP.

   The next in line was Microsoft Windows 98 released in June 1998.
   Substantially criticized for its slowness compared with Windows 95,
   many of its basic problems were later rectified with the release of
   Windows 98 Second Edition in 1999.

   As part of its professional line, Microsoft released Windows 2000 in
   February 2000. The consumer version following Windows 98 was Windows Me
   (Windows Millennium Edition). Released in September 2000, Windows Me
   attempted to implement a number of new technologies for Microsoft: most
   notably publicized was " Universal Plug and Play." However, the OS was
   substantially criticized for its lack of compatibility and stability.

   In October 2001, Microsoft released Windows XP, a version built on the
   Windows NT kernel that also retained the consumer-oriented usability of
   Windows 95 and its successors. This new version was widely praised in
   computer magazines. It shipped in two distinct editions, "Home" and
   "Professional", the former lacking many of the superior security and
   networking features of the Professional edition. Additionally, the
   "Media Centre" edition was released in 2003, with an emphasis on
   support for DVD and TV functionality including program recording and a
   remote control.

   In April 2003, Windows Server 2003 was introduced, replacing the
   Windows 2000 line of server products with a number of new features and
   a strong focus on security; this was followed in December 2005 by
   Windows Server 2003 R2.

   Windows Vista, the successor to Windows XP, is due to be released on
   January 30, 2007. Windows Server 2003's successor will be Windows
   Server "Longhorn", and has a planned release date in the second half of
   2007.

Security

   Security has been a hot topic with Windows for many years, and even
   Microsoft itself has been the victim of security breaches. Due in some
   part to the widespread usage of Windows on personal computers, as well
   as a number of technical reasons there is reportedly a five-fold
   greater amount of malware for Windows than other operating systems such
   as GNU/ Linux, Unix, Mac OS X, and FreeBSD. Windows was originally
   designed for ease-of-use on a single-user PC without a network
   connection, and did not have security features built in from the
   outset. Windows NT and its successors are designed for security
   (including on a network) and multi-user PCs, but was not designed for
   Internet security in mind as much since, when it was first developed,
   the Internet was less important. Combined with occasionally flawed code
   (such as buffer overflows), Windows is a frequent target of worms and
   virus writers. Furthermore, until Windows Server 2003 most versions of
   even Windows NT were shipped with important security features disabled
   by default, and vulnerable (albeit useful) system services enabled by
   default. In June 2005, Bruce Schneier's Counterpane Internet Security
   reported that it had seen over 1,000 new viruses and worms in the
   previous six months.

   Microsoft publicly admitted their ongoing security problems shortly
   after the turn of the century and now claims to regard security as
   their number one priority. The much-needed Automatic Update came first
   with Windows Me. As a result, Service Pack 2 for Windows XP, as well as
   Windows Server 2003, was installed by users more quickly than it might
   have been. Microsoft releases security patches through its Windows
   Update service approximately once a month (usually the second Tuesday
   of the month), although critical updates are made available at shorter
   intervals when necessary. In Windows 2000 (SP3 and later), Windows XP
   and Windows Server 2003, updates can be automatically downloaded and
   installed if the user selects to do so.

Windows Defender

   On 6 January 2005, Microsoft released a beta version of Windows
   AntiSpyware, based upon the previously released Giant AntiSpyware. On
   14 February 2006, Windows AntiSpyware became Windows Defender with the
   release of beta 2. Windows Defender is a freeware program designed to
   protect against spyware and other unwanted software.

   Paul Thurrott's Supersite for Windows gave Defender Beta 2 a stellar
   review; it received more middling reviews from other publications such
   as PC Magazine. and CNet. Windows 2000 and Windows XP users can freely
   download the program from Microsoft's web site, and Microsoft has
   stated that Windows Defender will ship as part of Windows Vista.

Third-party analysis

   A study conducted by Kevin Mitnick and marketing communications firm
   Avantgarde found that an unprotected and unpatched Windows XP system
   lasted only 4 minutes on the Internet before it was compromised. The
   AOL National Cyber Security Alliance Online Safety Study of October
   2004 determined that 80% of Windows users were infected by at least one
   spyware/ adware product. Much documentation is available describing how
   to increase the security of Microsoft Windows products. Typical
   suggestions include deploying Microsoft Windows behind a hardware or
   software firewall, running anti-virus and anti-spyware software, and
   installing patches as they become available through Windows Update.

Emulation software

   Emulation allows the use of some Windows applications without using
   Microsoft Windows. These include:
     * Wine – (Wine Is Not an Emulator) an almost complete free software/
       open-source software implementation of the Windows API, allowing
       one to run most Windows applications on x86 Unix-based platforms,
       including GNU/Linux.
     * CrossOver Office – a commercially packaged Wine with licensed
       fonts. Its developers are regular contributors to Wine, and focus
       on Wine running officially supported applications.
     * Cedega (formerly known as WineX) – TransGaming Technologies'
       proprietary fork of Wine, which is designed specifically for
       running games written for Microsoft Windows under GNU/ Linux.
     * ReactOS – open-source operating system, aimed to be compatible with
       existing Windows NT applications and drivers.
     * Project David – ambitious and controversial project to fully
       emulate Windows programs to run on other OSs.
     * Parallels Workstation - by Parallels, Inc.
     * Virtual PC - Virtual PC for Mac OS X is an emulation suite, and
       Virtual PC for Windows is a virtualization suite. The software was
       originally written by Connectix, and was subsequently acquired by
       Microsoft. Virtual PC for Mac emulates an x86-32 CPU, therefore can
       also support other OSs, but has specific support for Windows.
     * Darwine - this project intends to port and develop Wine as well as
       other supporting tools that will allow Darwin and Mac OS X users to
       run Microsoft Windows Applications, and to provide Win32 API
       compatibility at application source code level.

   Retrieved from " http://en.wikipedia.org/wiki/Microsoft_Windows"
   This reference article is mainly selected from the English Wikipedia
   with only minor checks and changes (see www.wikipedia.org for details
   of authors and sources) and is available under the GNU Free
   Documentation License. See also our Disclaimer.
