Understanding of Windows 2.0 most complete

Windows 2.0
Windows version 2 came out on December 9, 1987, and became little more popular than its predecessor. Most gained in popularity because of of its proximity to graphical applications made by Microsoft, Microsoft Excel for Windows and Microsoft Word for Windows. Windows applications can be run from MS-DOS, and then enter Windows to do the the operation, and will come out by itself when the application is closed.
Microsoft Windows finally gained a significant improvement when Aldus PageMaker appeared in versions for Windows, which previous could only run on the Macintosh. Some computer historians record this as the emergence of a significant application behavior apart by Microsoft as early success of Windows.
Windows version 2.0x using real-mode memory model, which is only able to access up to 1 megabyte of memory. In such configurations, Windows can run other apps multitasking, sort DESQview, which running in protected mode offered by the Intel 80286.
Windows 2.1
Furthermore, two new versions released, the Windows / 286 2.1 and Windows / 386 2.1. As with previous versions of Windows, Windows / 286 using real-mode memory model, but it was the first version to support the High Memory Area (HMA). Windows / 386 2.1 has a kernel running in protected mode to the emulation Expanded Memory Specification (EMS) standard Lotus-Intel-Microsoft (LIM), the predecessor specifications Extended Memory Specification (XMS) which would finally change the topology of computing in the IBM PC. All Windows and DOS-based application while it is running in real mode, which goes over the protected mode kernel by using the virtual 8086 mode, which is a new feature which owned by the Intel 80386.
2:03 version 3.0 and subsequently versions getting demands from Apple because it is version 2.1 has the appearance of a window in cascade mode (stacked), in addition to several features the Apple Macintosh operating system which "emulated" by Windows, its main is a problem the display / look and feel. Judge William Schwarzer ended up canceling the all 189 charges, except 9 charges filed by Apple against Microsoft on January 5, 1989.