Windows 95 is a consumer-oriented graphical user interface-based operating system. It was released on August 24, 1995 byMicrosoft, and was a significant progression from the company’s previous Windows products. During development, it was referred to as Windows 4.0 or by the internal codename Chicago.

Windows 95 integrated Microsoft’s formerly separate MS-DOS and Windows products. It featured significant improvements over its predecessor, Windows 3.1, most notably in the graphical user interface (GUI) and in its relatively simplified “plug-n-play” features. There were also major changes made at lower levels of the operating system, such as moving from a mainly 16-bit architecture to a pre-emptively multitasked 32-bit architecture.

Info gleaned from Wikipedia