Microsoft Windows 98 Microsoft Windows 98 is an operating system and its predecessor was Windows 95. An operating system is the interface between you and the computer, which helps manage files and makes using your personal computer simple and easy. While this release was not as big as Windows 95, Windows 98 contains significant updates, fixes, and support for new peripherals. Features like improved protection and better support make Windows 98 a quality upgrade. A new type of file system called