Windows 3.0 is the third major release of Microsoft Windows, and was released on 22 May 1990. It became the first widely successful version of Windows and a rival to Apple Macintosh and the Commodore Amiga on the GUI front. It was followed by Windows 3.1.
Windows 3.0 succeeded Windows 2.1x and included a significantly revamped user interface as well as technical improvements to make better use of the memory management capabilities of Intel's 80286 and 80386 processors. Text-mode programs written for MS-DOS could be run within a window (a feature previously available in a more limited form with Windows/386 2.1), making the system usable as a crude multitasking base for legacy programs. However, this was of limited use for the home market, where most games and entertainment programs continued to require raw DOS access.
The MS-DOS Executive file manager/program launcher was replaced with the icon-based Program Manager and the list-based File Manager, thereby simplifying the launching of applications. The MS-DOS Executive is also included as an alternative to these. The Control Panel, previously available as a standard-looking applet, was re-modeled after the one in Mac OS. It centralized system settings, including limited control over the color scheme of the interface.
A number of simple applications were included, such as the text editor Notepad and the word processor Write (both inherited from earlier versions of Windows), a macro recorder (new; later dropped), the paint program Paintbrush (inherited but substantially improved), and a calculator (also inherited). Also, the earlier Reversi game was complemented with the card game Solitaire.
The Windows icons and graphics were redesigned to take advantage of VGA's 16-color mode. Earlier versions only supported eight colors though could run on monochrome video adapters. Windows 3.0 also allowed the user to use a 256 color video adapter, whereas previous versions only supported 16 colors.
Windows 3.0 includes a Protected/Enhanced mode which allows Windows applications to use more memory in a more painless manner than their DOS counterparts could. It can run in any of Real, Standard, or 386 Enhanced modes, and is compatible with any Intel processor from the 8086/8088 up to 80286 and 80386. Windows 3.0 tries to auto detect which mode to run in, although it can be forced to run in a specific mode using the switches: /r (real mode), /s ("standard" 286 protected mode) and /3 (386 enhanced protected mode) respectively. Due to this backward compatibility of the whole system, Windows 3.0 applications also must be compiled for 16-bit mode, without ever using the full 32-bit capabilities of the 386 CPU.
This was the first version to run Windows programs in protected mode, although the 386 enhanced mode kernel was an enhanced version of the protected mode kernel for Windows/286.
A "multimedia" version, Windows 3.0 with Multimedia Extensions 1.0, was released later in 1991. This was bundled with "multimedia upgrade kits", comprising a CD-ROM drive and a sound card, such as the Creative Labs Sound Blaster Pro. This version was the precursor to the multimedia features available in Windows 3.1 and later, and was part of Microsoft's specification for the Multimedia PC.
Windows 3.0 was the last version of Windows to advertise 100% compatibility with older Windows applications. This only applies to real mode.