Windows 95 is a consumer operating system developed by Microsoft as part of the Windows 9x family of operating systems. Windows 95 has previously combined separate MS-DOS and Microsoft Windows products into one unit. The system contained significant improvements over its predecessor, particularly in the graphical user interface (GUI) and simplified plug-and-play functions. Major changes were also made to the basic components of the operating system, such as the transition from a mainly 16-bit multitasking architecture to a 32-bit multitasking architecture in advance, at least when running only 32-bit applications in protected mode. With an extensive marketing campaign, Windows 95 introduced many features and functions that appeared in later versions of Windows, such as the taskbar, the "Start" button and an improved user desktop.
After the RTM version, Windows 95 was released in three paid updates:
95A/OSR1- The version was a standalone version of Windows 95 RTM with Service Pack 1. Internet Explorer 2.0 and infrared (IrDA) support were added.
95B/OSR2- In OSR2 version a refreshed loading screen appears with "Microsoft Internet Explorer" added. Internet Explorer version 3.0 is integrated with the system. The system includes updated MS-DOS to version 7.1, support for FAT32, Ultra-DMA, MMX prosessors and DirectX library version 2.0a. In OSR2 version there was an optional support for USB.
95C/OSR2.5- OSR version 2.5 includes technologies developed by Nashville project, updated Internet Explorer 4 and DirectX 5 libraries.