Released on 22 May 1990, Windows 3.0 marked the beginning of Microsoft's road to dominating the desktop computer market. Compared to its predecessor, it featured a completely new interface, support for the new memory management capabilities of the then-new 80286 and 80386 processors, as well as support for running DOS programs in windows within Windows. It also came with a simple digital version of Solitaire, making this card game a prerequisite for any desktop operating system.
For most people, Windows 3.x was their first encounter with Windows, seeing Windows 2.x and 1.x weren't very popular. Windows 3.0 was the first Windows OS to be bundled by PC manufacturers, allowing them to compete with Apple's Macintosh. Even though you'll be hard-pressed to find anyone still running Windows 3.x as their main operating system, it was still sold as an embedded operating system by Microsoft to power cash registers and in-flight entertainment systems on some Virgin and Quantas aeroplanes. Regular support ended late 2001.
Despite its limitations, I think many of us will look back on Windows 3.x with a bit of fondness (Stockholm Syndrome-induced or not). As I was reading through the manual during the writing of this news item, I encountered many things that we take fro granted now - the manual explains icons, windows, dialog boxes, menu bars, cursors, everything. How time flies.