The Installable File System by its English acronym IFS (Installable File System) consists of a file system API in the operating systems: IBM, OS / 2, and Microsoft Windows NT; which allows them to recognize and load drivers. History
When IBM and Microsoft were developing the OS / 2 code, they realized that the version of their FAT file system was not good enough for hard disks and started developing the High Performance File System HPFS) codenamed Pinball. Instead of coding it inside the kernel as FAT was, Microsoft developed a driver-based API that would allow them and other developers to add new file systems to the kernel without the need to modify it.
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