Microsoft had added some new featurea to the .net framework.within these ".net framework service pack1"is one thing and also it had the windows presentation foundation.i want to tell u about wpf.
Performance improvements have been made to Windows Presentation Foundation, including a faster startup time and improved performance for Bitmap effects. Additional functionality for Windows Presentation Foundation includes better support for line of business applications, native splash screen support, DirectX pixel shader support, and the new WebBrowser control.
Windows/286 2.1 was simply the next version of Windows 2.03. In 1987, there was Windows 2.0 and Windows/386. The successor products in 1988 were Windows/286 2.1 and Windows/386 2.1. And later (in 1989) there was version 2.11 of both. The version was super confusing, and I don't think even people at Microsoft understood it.