0 Windows® Family

Microsoft has began at 1981 with MSDOS 1.0 to develop operating systems for computers. One year ahead Microsoft has worked in cooperation on the Unix derivative operating system XENIX OS for different computer platforms, this OS field however was transferred to SCO in 1984. With Windows 1.0 were added in 1985 beside DOS a second OS line, which was meant first for single workplaces for Consumer (Home edition) and later with added network support. 

The third product line was started with MS OS/2 1.0 in 1987. The professional edition was for server applications and network clients designed. In February 1989 the development of Windows NT started (NT = New Technology), the first version was published with Windows NT 3.1 in July 1993. Up to 200 developers had programmed at the same time on the approx. 6 million code lines. While MS-DOS was programmed nearly completely in assembler, Windows NT also consists of source code of the programming language C. Up to 450 developers were involved at the operating system Windows NT 3.51 which was released in May 1995. To record times up to 800 developers worked on the successor Windows NT 4.0 for the release in July 1996. Windows 2000 was the ambitious project following on this, up to 1.400 developer worked on the 29 million code lines. The development costs amounted to about 1 billion dollar. Altogether 5.000 developers worked on the 50 million code lines of assemblers, C and C++, for the Windows Server 2003 operating system with release in April 2003. The development of operating system versions for the MIPS, PowerPC and alpha architecture became gradually cancelled up to the market release of Windows 2000. This was also involved by the lacking driver and software support for these platforms. 

With Windows CE 1.0 a new product line for small devices (PDAs) was created in 1996. 

The former splitting into Consumer and Business Windows Edition is to be united with Windows XP (alias Whistler) again and continued in this product line. Thus is void for the first time the condition of MSDOS, which need even Windows 95 to ME for the system start. Directly with all Windows versions so far the drive assembly marking with the letters [A to Z] whereby the maximally managable number on 26 is limited, exluded mounted network directorys. 

Windows 1.0

Windows 3.11

Windows 95

Windows 98

Windows NT 3.1

Windows NT 4.0

Windows 2000

Windows XP

Windows Vista

Windows Server 2003 

Driver models

MSDOS contains simplest hardware drivers for the access to harddisks, floppy disk drives, file system, serial and parallel interfaces, which do not correspond to todays modern hardware. As example color printers can be used to print text by commandline instruction but aren`t controllable in print quality or color. Hardware drivers can be loaded only statically and are active also without use loaded up to the restart. 

- only 16-bit material mode driver 

- only direct hardware access possible (caused by the single tasking system) 

With Windows 3.x uniform interfaces were made available for the first time for applications and drivers. Driver formats of Windows 3.x are 386, drv and dll files. 

Under Windows 95 to ME are a large amount of drivers from Windows 3.11 applicable, however that slows down the 16-bit driver by the frequent access changes between real mode into the protected mode for 32-bit driver. 

In addition the new driver format vxd, which runs completely in the protect mode, cames with the ability to be loaded dynamic at requirement, depending on the driver type. New function for Windows is the Plug&Play support of hardware devices, standard drivers are attached to the operating system. The WDM driver model is provided for the standardization of drivers for Windows 98 and following operating systems, so far only for devices at the USB or Firewire channel. 

Windows NT makes the setup of device services possible, alternatively with manual or automatic start or the complete deactivation of the service. The driver format vdd (Virtual DEVICE Driver's) is available since Windows NT. The drivers are depending upon type separated in the user mode, in the Kernel mode with direct hardware access or also as virtual device drivers (VDD) of the operating system core. 

2006 should be the next Windows Version Vista with the code name "Longhorn" avaiable. All Windows Editions should be based on the same core and were extended by specific modules depending on the field