Windows 98 is an operating system developed by Microsoft as part of its Windows 9x family of Microsoft Windows operating systems. It is the successor to Windows 95, and was released to manufacturing on May 15, 1998, and generally to retail on June 25, 1998. Like its predecessor, it is a hybrid 16-bit and 32-bit monolithic product with the boot stage based on MS-DOS.
Windows 98 is a heavily web-integrated operating system that bears numerous similarities to its predecessor. It heavily relies on the HTML language. Most of the improvements are cosmetic or designed to improve the user experience, but there are a handful of features that enhance system functionality and capabilities. These include improved USB support and accessibility, as well as support for hardware advancements such as DVD players. It was the first Windows operating system to adopt the Windows Driver Model. It also introduced features that would become standard in future generations of Windows, such as Disk Cleanup, Windows Update, multi-monitor support, and Internet Connection Sharing.
Microsoft had marketed Windows 98 as a "tune-up" to Windows 95, rather than an entirely improved next generation of Windows. Upon release, it was generally well received for its web-integrated interface and ease of use, as well as for addressing issues that had been present in Windows 95, though users had pointed out that it was not significantly more stable than its predecessor. It saw one major update called Windows 98 Second Edition (SE) on May 5, 1999, and was succeeded by Windows Me in 2000. It sold an estimated 58 million licenses, and Microsoft ended mainstream support for both Windows 98 and 98 SE on June 30, 2002, and ended extended support on July 11, 2006.
Following the success of Windows 95, development of Windows 98 began, initially under the development codename "Memphis." The first test version, Windows Memphis Developer Release, was released in January 1997.