Windows NT 3.1 in 1993

When Microsoft Windows NT was released to manufacturing on July 27, 1993, Microsoft met an important milestone: the completion of a project begun in the late 1980s to build an advanced new operating system from scratch.

Windows NT represents nothing less than a fundamental change in the way that companies can address their business computing requirements," Microsoft Chairman Bill Gates said at its release. 

That change is represented in the product's name: NT stands for new technology. To maintain consistency with Windows 3.1, a well-established home and business operating system at the time, the new Windows NT operating system began with version 3.1. Unlike Windows 3.1, however, Windows NT 3.1 was a 32-bit operating system.

Windows NT was the first Windows operating system to combine support for high-end, client/server business applications with the industry's leading personal productivity applications. It was initially available in both a desktop (workstation) version and a server version called Windows NT Advanced Server. 

The desktop version was well received by developers because of its security, stability, and Microsoft Win32 application programming interface (API)—a combination that made it easier to support powerful programs. 

The result was a strategic business platform that could also function as a technical workstation to run high-end engineering and scientific applications.

Windows NT 3.1 contained overlapping windows and other features similar to Windows 3.1.

In addition, the operating system broke new ground in security, operating system power, performance, desktop scalability, and reliability. 

New features included a preemptive multitasking scheduler for Windows–based applications, integrated networking, domain server security, OS/2 and POSIX subsystems, support for multiple processor architectures, and the NTFS file system.