DPMI

DPMI, or DOS Protected Mode Interface, is a software standard developed by Phar Lap Software in the late 1980s and early 1990s. It was designed to allow DOS applications to run in protected mode, a more advanced mode of operation for x86 processors that provides better memory management and multitasking capabilities compared to the real mode used by traditional DOS applications.

The DPMI standard defines a set of services that can be called by DOS applications to perform tasks such as allocating and freeing memory, creating and managing tasks, and handling interrupts. These services are provided by a DPMI host, which is a piece of software that runs in protected mode and manages the resources of the system.

DPMI was widely adopted by DOS developers as a way to create more advanced and efficient applications. It allowed developers to take advantage of the features of protected mode, such as the ability to access more memory and to run multiple applications simultaneously.

However, with the rise of Windows and other modern operating systems, DPMI has largely fallen out of use. Today, it is primarily of historical interest, but it played a significant role in the development of DOS applications and the evolution of the x86 architecture.