Microsoft's premiere object-oriented programming language, which was used to build Microsoft Office, Internet Explorer, and many of Microsoft's other commercial applications and operating system components. Visual C++ was also used to build Netscape Navigator, Lotus Notes, and Corel's WordPerfect Suite. The NT database servers from Oracle, Sybase, Informix and Microsoft were all built in Visual C++. A major component of Microsoft's Visual C++ programming environment is the accompanying Microsoft Foundation Class Library (MFC). The Visual C++ environment also includes an impressive array of tightly integrated programming tools, such as a debugger, project and source code management, and a host of other facilities that comprise Microsoft's Visual Studio developer's suite.