Complex sentence: This approach allowed instantaneous task switching in the otherwise-single-tasking DOS operating system, and its window-based interface echoed (in text format) that of the Apple Macintosh, and anticipated the eventual look of Microsoft Windows 2.0.
Split into simpler sentences: This approach allowed instantaneous task switching in the otherwise-single-tasking DOS operating system. Although a text mode program, its window-based interface echoed that of the Apple Macintosh, and anticipated the eventual look of Microsoft Windows 2.0.