The Windows system enables users to interact with the computer in an intuitive way by clicking on graphical windows. This is in contrast to the more traditional command-line interface.
The Windows kernel, known as the Executive, provides multiprocessor synchronization, thread and interrupt scheduling and dispatching and trap handling and exception dispatching. It also handles initializing device drivers at bootup.
Windows 1.0
Windows 1.0 was Microsoft’s first graphical operating system. It was released to manufacturing on November 20, 1985 and made available internationally in May 1986. It features overlapping windows, drop-down menus and scroll bars. It also supports both existing MS-DOS applications and graphical programs designed for Windows. Unlike later versions of Windows, it manages windows by tiling rather than stacking them (a design decision based on user-testing data from Xerox PARC, where some of the original developers were employed).
Despite positive reactions to the early presentations and support from various hardware and software vendors, Windows 1.0 was widely criticized for high system requirements, focusing on mouse input at a time when keyboard usage was dominant, and slow performance. On December 31, 2001, Microsoft declared Windows 1.0 obsolete and stopped providing support for it.
Windows NT
Windows NT is a multi-tasking operating system that supports multiple user accounts. It provides security through passwords and encryption. It features a hardware abstraction layer that hides the specific intricacies of an underlying CPU and motherboard from the kernel. It supports different processor architectures through symmetric multiprocessing technology.
It uses a kernel that executes in privileged mode and has access to all system resources. It manages virtual memory and supports networked workstations. It also features a graphical user interface.
NT is the first purely 32-bit version of Microsoft Windows. Its previous consumer-oriented counterparts, Windows 3.1x and Windows 9x, were 16-bit/32-bit hybrids. NT supports various hardware platforms, including Intel x86 and DEC Alpha. It is interoperable with a variety of network operating systems, such as UNIX and Novell Netware.
Windows XP
XP was Microsoft’s most successful version of Windows to date. It came out in 2001 and was a major improvement over Windows ME, which had been released six years earlier. XP featured improved performance and stability, a better user interface, increased hardware support, and expanded multimedia capabilities.
In addition, XP introduced the Taskbar and System Tray or Notification Area, which contains your computer’s settings, status, and application windows. XP also had a new error reporting feature that removed the infamous blue screen of death and instead displayed a small popup box asking for feedback.
In April 2014, Microsoft ended support for XP, meaning that the operating system would no longer receive software updates or bug fixes. Despite this, many people still use the OS.
Windows ME
Windows ME (Millennium Edition) is a 16-bit consumer operating system that succeeded Microsoft’s previous versions of Windows, including the very popular Windows 98. Like its predecessors, it is based on the MS-DOS kernel but restricts access to real mode DOS to cut boot times. It also includes some improvements from Microsoft’s business-oriented Windows 2000, such as System Restore and Windows Movie Maker.
It’s the first home consumer version of Windows to fuse spectacular intuitive properties with stability that inspired confidence. However, ME had one major drawback: It restricted access to real-mode DOS, which meant that some old software programs could no longer run. It also removed some features from NT-based versions of Windows that were used in enterprise environments, such as Explorer Web View and Personalized Menus.
Windows 10
Windows 10 is the latest version of Microsoft’s flagship operating system. It builds on Windows 8 and 7 by combining a mobile-friendly design with desktop and touch-friendly features. It also includes the personal assistant Cortana.
The operating system updates automatically using Windows Update. IT professionals can control how and when Windows 10 devices receive updates by selecting an Insider release ring.
The Fast ring provides early access to development builds, while the Slow ring lets IT departments qualify updates for application compatibility. For business users, the Current Branch for Business allows IT to delay major releases until they’re ready. IT can also use Group Policy to disable updates or to control how they install on hardware. The OS also supports multiple ways to log in, including fingerprint scanning, iris scans and facial recognition technology.