Windows is a family of operating systems for personal computers developed by Microsoft. Windows are currently running on about 90% of the personal computer worldwide. Windows provides a graphical user interface (GUI), virtual memory management, multitasking, and support for many peripheral devices.
Windows started as a 16-bit Operating environment. They use MS-DOS for filesystem services but have their own executable file format and provide their own device drivers (graphics, printer, mouse, keyboard and sound). They allow the user to (non-preemptively) multi-task graphical applications. They implement an elaborated segment-based software virtual memory scheme, which allows to run applications larger than available memory. Examples include Windows 1.0 (1985) and Windows 2.0 (1987) and its close relative Windows/286.
Later Windows migrated to a Hybrid 16/32-bit operating environment. Windows/386 introduced a 32-bit protected mode kernel and virtual machine monitor. For the duration of a Windows session, it provided a device virtualization for the disk controller, video card, keyboard, mouse, timer and interrupt controller. The user-visible consequence was that it became possible to preemptively multitask multiple MS-DOS environments in separate windows. Windows applications were still multi-tasked cooperatively inside one of such real-mode environments. Windows 3.0 (1990) and Windows 3.1 (1992) are examples of this design.
The Hybrid 16/32-bit operating environment advanced into Hybrid 16/32-bit operating system 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. There were three releases of Windows 95 and then Windows 98. In 2000, Microsoft released Windows ME, which used the same core as Windows 98 but adopted the visual appearance of Windows 2000.
32-bit operating systems originally designed and marketed for higher-reliability business use with no DOS heritage. The first release was Windows NT 3.1, which was followed by NT 3.5 (1994), NT 3.51 (1995) and NT 4.0 (1996). Windows CE, Microsoft's offering in the mobile and embedded markets, is also a true 32-bit operating system.
64-bit operating systems are designed for AMD's AMD64 CPU architecture and Intel'sArchitecture 64-bit. The 64-bit Windows family comprises Windows XP 64 Bit Edition and Windows Server 2003; as yet neither has entered Microsoft's core consumer market.
The following is a list of all current version of Windows Operating Systems:
- Windows CE for embedded systems: Pocket PC (PDAs), Smartphone, Handheld PC, Portable Media Players
- Windows XP (Home and professional) for desktops and notebooks
- Windows Server 2003 for servers
- Windows XP Embedded for embedded systems
The following are the past versions of Windows:
DOS Based: Windows 1.0 (1985), Windows 2.0 (1987), Windows 3.0 (1990), Windows 3.1 (1992),Windows 95 (1995), Windows Millennium Edition (Me) (2000)
NT Kernel Based: Windows NT 3.1 (1993), Windows NT 3.5 (1994), Windows NT 3.51 (1995), Windows NT 4.0 (1996), Windows 2000 (2000)
Related Terms: Microsoft DOS, Windows CE, Windows 95, Windows 98, Windows 2000, Windows CE, Windows XP, Windows 2003, Windows NT