Environmental Subsystems

Environmental Subsystems are components of the Microsoft Windows operating systems that support the running of applications from different operating system architectures.

What is Environmental Subsystems?

Components of the Microsoft Windows NT or Windows 2000 operating system that support the running of applications from different operating system architectures. Environmental subsystems provide the necessary “environment” in which these applications can run. They are an essential part of the Windows NT operating system that enables cross-platform support for applications written for different operating systems.

Windows NT and Windows 2000 include the following environmental subsystems:

  • Win32 subsystem for running 32-bit Windows applications
  • OS/2 subsystem for running OS/2 1.X character-based applications (does not support the OS/2 Presentation Manager GUI or Warp versions)
  • POSIX subsystem for running POSIX.1-compliant applications
NOTE

MS-DOS-based applications run on Windows NT in the context of a Win32 application called a Virtual DOS Machine (VDM) that emulates an MS-DOS environment.