Windows 95 is the fundation of the “modern” Windows. It was based on the old MS-DOS 6.22, that was on 16 bit, but had his own 32 bit drivers and, the first from Microsoft, it included drivers for several hardware platforms that were used by the major computer manufacturers. It still didn’t recognized alot of hardware, but, a lucky few didn’t had that problem.
Since it was built on top of MS-DOS, you could still load the old drivers for use in MS-DOS applications via config.sys/autoexec.bat. This remained until Windows 98SE was replaced by the MAJOR failure Windows ME (Millenium)
Windows 95 also introduced directX for gaming 3D acceleration. This lead to the simplification of game development since the programmers didn’t have to do the game development on specific graphic cards, but focus on directX functions and directX would take the role of an interface between games and different graphic cards. Until directX came, games had 2, 3 or more executables, one for cards without 3D acceleration, one for S3 cards, one for 3dfx cards and maybe one for d3d (direct 3D from directX)
One of the nice things that directX did, was to compensate the lack of 3D functions in a graphic card with processor calculated ones. That was a good thing, but it had the disadvantage that if the game would need some processor power, the graphics will suffer.