Microsoft Windows CE is a 32-bit real-time embedded operating system (RTOS) designed from the ground up to empower the development of a new range of emerging computing appliances, including set-top boxes, digital versatile disc (DVD) drives, entertainment consoles, smart phones, highly portable and personal computing devices like handheld computers, and home appliances. Windows CE is modular, allowing use of a minimum set of software components needed to support receiver requirements. This uses less memory and improves operating system performance. Windows CE provides a subset of the Win32 application program interface (API) set, which provides an effective amount of application source-code level portability and compatibility and user interface consistency with other Microsoft Windows operating systems and Windows applications. See also: Java.