Windows NT (New Technology)

Windows NT (New Technology)

Bottomline: Microsoft had DOS based OS, OS1 and GUI based OS OS/2 (which it renamed to NT after split with IBM). Both these were integrated in Windows XP for the 1st time

Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessingmulti-useroperating system. “NT” was expanded to “New Technology” for marketing purposes but no longer carries any specific meaning. It was intended to complement consumer versions of Windows that were based on MS-DOS. NT was the first fully 32-bit version of Windows, whereas its consumer-oriented counterparts, Windows 3.1x and Windows 9x, were 16-bit/32-bit hybrids. Windows 2000Windows XPWindows Server 2003Windows Vista,Windows Home ServerWindows Server 2008Windows 7Windows Server 2008 R2Windows 8Windows Phone 8Windows RT and Windows Server 2012 are members of the Windows NT family, although they are not branded using the name “Windows NT”

Microsoft decided to create a portable operating system, compatible with OS/2 and POSIX and supporting multiprocessing, in October 1988.[14] When development started in November 1989, Windows NT was to be known as OS/2 3.0,[15] the third version of the operating system developed jointly by Microsoft and IBM. To ensure portability, initial development was targeted at the Intel i860XR RISC processor, switching to the MIPS R3000 in late 1989, and then the Intel i386 in 1990.[16] Microsoft also continued parallel development of the DOS-based and less resource-demanding Windows environment, resulting in the release of Windows 3.0 in May 1990. Windows 3 was eventually so successful that Microsoft decided to change the primaryapplication programming interface for the still unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API. This decision caused tension between Microsoft and IBM and the collaboration ultimately fell apart. IBM continued OS/2 development alone while Microsoft continued work on the newly renamed Windows NT. Though neither operating system would immediately be as popular as Microsoft’s MS-DOS or Windows products, Windows NT would eventually be far more successful than OS/2.

Microsoft hired a group of developers from Digital Equipment Corporation led by Dave Cutler to build Windows NT, and many elements of the design reflect earlier DEC experience with Cutler’s VMS[17] and RSX-11. The operating system was designed to run on multiple instruction set architectures and multiple hardware platforms within each architecture. The platform dependencies are largely hidden from the rest of the system by a kernel mode module called the HAL (Hardware Abstraction Layer).

Windows NT’s kernel mode code further distinguishes between the “kernel”, whose primary purpose is to implement processor and architecture dependent functions, and the “executive”. This was designed as a modified microkernel, as the Windows NT kernel was influenced by the Mach microkernel developed at Carnegie Mellon University,[18] but does not meet all of the criteria of a pure microkernel. Both the kernel and the executive are linked together into the single loaded module ntoskrnl.exe; from outside this module there is little distinction between the kernel and the executive. Routines from each are directly accessible, as for example from kernel-mode device drivers.

API sets in the Windows NT family are implemented as subsystems atop the publicly undocumented “native” API; this allowed the late adoption of the Windows API (into the Win32 subsystem). Windows NT was one of the earliest operating systems to use Unicode internally.

Supported platforms[edit]

NT was written in C and C++,[36] and is reasonably portable, although (as of 2009) only three architectures are currently supported. That said, it proved far more difficult to port applications such as Microsoft Office which were sensitive to issues such as data structure alignment onRISC processors. Unlike Windows CE which routinely runs on a variety of processors, the lack of success of RISC-based systems in the desktop market has resulted in nearly all NT deployments being on x86 architecture processors.

 

http://en.wikipedia.org/wiki/Architecture_of_Windows_NT

Bottomline: Microsoft had DOS based OS, OS1 and GUI based OS OS/2 (which it renamed to NT after split with IBM). Both these were integrated in Windows XP for the 1st time

Windows NT is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. It was a powerful high-level-language-based, processor-independent, multiprocessingmulti-useroperating system. “NT” was expanded to “New Technology” for marketing purposes but no longer carries any specific meaning. It was intended to complement consumer versions of Windows that were based on MS-DOS. NT was the first fully 32-bit version of Windows, whereas its consumer-oriented counterparts, Windows 3.1x and Windows 9x, were 16-bit/32-bit hybrids. Windows 2000Windows XPWindows Server 2003Windows Vista,Windows Home ServerWindows Server 2008Windows 7Windows Server 2008 R2Windows 8Windows Phone 8Windows RT and Windows Server 2012 are members of the Windows NT family, although they are not branded using the name “Windows NT”

Microsoft decided to create a portable operating system, compatible with OS/2 and POSIX and supporting multiprocessing, in October 1988.[14] When development started in November 1989, Windows NT was to be known as OS/2 3.0,[15] the third version of the operating system developed jointly by Microsoft and IBM. To ensure portability, initial development was targeted at the Intel i860XR RISC processor, switching to the MIPS R3000 in late 1989, and then the Intel i386 in 1990.[16] Microsoft also continued parallel development of the DOS-based and less resource-demanding Windows environment, resulting in the release of Windows 3.0 in May 1990. Windows 3 was eventually so successful that Microsoft decided to change the primaryapplication programming interface for the still unreleased NT OS/2 (as it was then known) from an extended OS/2 API to an extended Windows API. This decision caused tension between Microsoft and IBM and the collaboration ultimately fell apart. IBM continued OS/2 development alone while Microsoft continued work on the newly renamed Windows NT. Though neither operating system would immediately be as popular as Microsoft’s MS-DOS or Windows products, Windows NT would eventually be far more successful than OS/2.

Microsoft hired a group of developers from Digital Equipment Corporation led by Dave Cutler to build Windows NT, and many elements of the design reflect earlier DEC experience with Cutler’s VMS[17] and RSX-11. The operating system was designed to run on multiple instruction set architectures and multiple hardware platforms within each architecture. The platform dependencies are largely hidden from the rest of the system by a kernel mode module called the HAL (Hardware Abstraction Layer).

Windows NT’s kernel mode code further distinguishes between the “kernel”, whose primary purpose is to implement processor and architecture dependent functions, and the “executive”. This was designed as a modified microkernel, as the Windows NT kernel was influenced by the Mach microkernel developed at Carnegie Mellon University,[18] but does not meet all of the criteria of a pure microkernel. Both the kernel and the executive are linked together into the single loaded module ntoskrnl.exe; from outside this module there is little distinction between the kernel and the executive. Routines from each are directly accessible, as for example from kernel-mode device drivers.

API sets in the Windows NT family are implemented as subsystems atop the publicly undocumented “native” API; this allowed the late adoption of the Windows API (into the Win32 subsystem). Windows NT was one of the earliest operating systems to use Unicode internally.

Supported platforms[edit]

NT was written in C and C++,[36] and is reasonably portable, although (as of 2009) only three architectures are currently supported. That said, it proved far more difficult to port applications such as Microsoft Office which were sensitive to issues such as data structure alignment onRISC processors. Unlike Windows CE which routinely runs on a variety of processors, the lack of success of RISC-based systems in the desktop market has resulted in nearly all NT deployments being on x86 architecture processors.

 

http://en.wikipedia.org/wiki/Architecture_of_Windows_NT

History of Windows

History of Windows

in 1983,[1] Microsoft announced the development of Windows, a graphical user interface (GUI) for its own operating system (MS-DOS). The product line has changed from a GUI product to a modern operating system over two families of design, each with its own codebase and default file system.

The 3.x and 4.x family includes Windows 3.0Windows 3.1xWindows 95Windows 98, and Windows MEWindows for Workgroups 3.11 added 32-bit networking and 32-bit disk access. Windows 95 added additional 32-bit capabilities (however, MS-DOS, some of the kernel, and supplementary utilities such as Disk Defragment remained 16-bit) and implemented a new object oriented user interface, elements of which are still used today.

The Windows NT family started with Windows NT 3.1 in 1993. Modern Windows operating system versions are based on the newer Windows NT kernel that was originally intended for OS/2. Windows runs on IA-32x86-64, and in Windows RT on 32-bit ARM (ARMv7) processors.[2][3] Earlier versions also ran on the i860AlphaMIPSFairchildClipperPowerPC, and Itanium architectures. Some work was done to port it to the SPARC architecture.

Windows XP[edit]

Windows XP desktop

Main articles: Windows XP and Features new to Windows XP

On 25 August 2001, Microsoft released Windows XP (codenamed “Whistler“). The merging of the Windows NT/2000 and Windows 95/98/Me lines was finally achieved with Windows XP. Windows XP uses the Windows NT 5.1 kernel, marking the entrance of the Windows NT core to the consumer market, to replace the aging 16/32-bit branch. The initial release met with considerable criticism, particularly in the area of security, leading to the release of three majorService Packs. Windows XP SP1 was released in September 2002, SP2 came out in August 2004 and SP3 came out in April 2008. Service Pack 2 provided significant improvements and encouraged widespread adoption of XP among both home and business users. Windows XP lasted longer as Microsoft’s flagship operating system than any other version of Windows, from 25 October 2001 to 30 January 2007 when it was succeeded by Windows Vista.

 

Windows Architecture

Windows-8-Platform-Architecture: http://www.bitcrazed.com/post/2012/01/27/An-Accurate-Windows-8-Platform-Architecture-Diagram.aspx

http://en.wikipedia.org/wiki/Windows_Runtime

WinRT applications natively support both the x86 and ARM architectures, and also run inside a sandboxed environment to allow for greater security and stability

http://en.wikipedia.org/wiki/Component_Object_Model

http://en.wikipedia.org/wiki/Object_Linking_and_Embedding

http://winsupersite.com/windows-8/windows-8-architecture-wars-part-1-clover-trail-vs-arm

http://blogs.msdn.com/b/b8/archive/2012/02/09/building-windows-for-the-arm-processor-architecture.aspx