Windows 2.0x
Windows 2.0 is a major release of Microsoft Windows, a family of graphical operating systems for personal computers developed by Microsoft. It was released to manufacturing on December 9, 1987, as a successor to Windows 1.0. Codenamed Nixa, the product includes two different variants, a base edition for 8086 real mode, and Windows/386, an enhanced edition for i386 protected mode. Windows 2.0 differs from its predecessor by allowing users to overlap and resize application windows, and the operating environment also introduced desktop icons, keyboard shortcuts, and support for 16-color VGA graphics. It also introduced Microsoft Word and  Excel, and integrated the Control Panel, while the developer support increased substantially. Noted as an improvement of its predecessor, Microsoft Windows gained more sales and popularity after its release, although it is also considered to be the incarnation that remained a work in progress. Due to the introduction of overlapping windows, Apple Inc. had filed a lawsuit against Microsoft in March 1988 after accusing them of violating copyrights Apple held, although in the end, the judge ruled in favor of Microsoft. The operating environment was succeeded by Windows 2.1 in May 1988, while Microsoft ended its support on December 31 , 2001. Release versions. The operating environment, codenamed Nixa, came in two different variants with different names and CPU support. The basic edition supported the 8086 mode of the 80386 microprocessor. It would be later renamed to "Windows/286" with the release of Windows 2.1 in 1988. Despite its name, the variant was fully operational on an 8088 or 8086 processor, although the high memory area would not be available on an 8086-class processor; however, expanded memory could still be used. IBM's PS/2 Model 25, which had an option to ship with a "DOS 4.00 and Windows kit" for educational  markets, shipped Windows with 8086 hardware. The other variant, "Windows/386" was available as early as September 1987, pre-dating the release of Windows 2.0 in December 1987. It was much more advanced than its other sibling. It introduced a protected mode kernel, above which the GUI and applications run as a virtual 8086 mode task. The variant had fully preemptive multitasking, and allowed several MS-DOS programs to run in parallel in "virtual 8086" CPU mode, rather than always suspending background applications. With the exception of a few kilobytes of overhead, each DOS application could use any available low memory  before Windows was started. Windows/386 ran Windows applications in a single Virtual 8086 box, with EMS emulation. Windows/386 also provided EMS emulation, using the memory management features of the i386 to make RAM beyond 640k behave like the banked memory previously only supplied by add-in cards and used by popular DOS applications. There was no support for disk-based virtual memory, so multiple DOS programs had to fit inside the available physical memory; therefore, Microsoft suggested buying additional memory and cards if necessary. Neither of these versions worked with DOS memory managers like CEMM or QEMM or with DOS  extenders, which have their own extended memory management and run in protected mode as well. This was remedied in version 3.0, which is compatible with Virtual Control Program Interface (VCPI) in "standard mode" and with DOS Protected Mode Interface (DPMI) in "386 enhanced" mode. Microsoft ended its support for Windows 2.0 on December 31, 2001. Features. Unlike its predecessor, Windows 2.0 allows user to overlap and resize application windows. It has also introduced desktop icons, keyboard shortcuts, and the terminology "minimize" and "maximize", as opposed to "iconize" and "zoom" which was used in Windows 1.0. Support for 16-color VGA  graphics, EMS memory, and new capabilities of the i386 CPU in some versions were also added. Windows 2.0 is the last version of Windows that ran solely on floppy disks. The operating environment is shipped with fifteen programs, and it also introduced graphical programs Microsoft Word and Excel, in order to compete against the then-reigning competitors WordPerfect and Lotus 1-2-3. Besides Aldus Pagemaker and CorelDRAW, there were not a lot of Windows-compatible applications available for Windows 2.0, although the developer support increased substantially. Most developers still maintained DOS versions of their applications, as Windows users were  still a minority of their market at this period of time. It is also the first Windows version to integrate the Control Panel and program information files. IBM licensed Windows's GUI for OS/2 as Presentation Manager, and the two companies stated that it and Windows 2.0 would be almost identical. System requirements. The official system requirements for Windows 2.0 include the following. Windows 2.0 was still dependent on the DOS system and it still hadn't passed the 1 MB mark in terms of the random-access memory. Reception. Windows 2.0 is considered to be an incremental improvement of  its predecessor, although, it is also considered to be the incarnation of Windows that still remained a work in progress. Due to its improvements, Microsoft Windows has gained more popularity after its release and its interface is considered to be easier-to-manage. "CNET" considers that Windows 2.0 wasn't too furbished in comparison with its predecessor. "BYTE" magazine listed the variant as among the "distinction" winner of the BYTE Awards in 1989, describing it as a "serious competition for OS/2" as it "taps into the power of the 80386". The operating environment costed $99. Sales of Microsoft Windows  reached one million in 1988, and by January 1990, it had reached less than two million, although Windows 2.0 was not widely used. It was succeeded by Windows 2.1, which was released in the United States and Canada in May 1988. Legal conflict with Apple. On March 17, 1988, Apple Inc. filed a lawsuit against Microsoft and Hewlett-Packard, accusing them of violating copyrights Apple held on the Macintosh System Software. Apple claimed the "look and feel" of the Macintosh operating system, taken as a whole, was protected by copyright and that Windows 2.0 violated this copyright by having the  same icons. The judge ruled in favor of Hewlett-Packard and Microsoft on all but 10 of the 189 graphical user interface elements on which Apple sued, and the court found the remaining 10 GUI elements could not be copyrighted.