MultiBoot is a standardized interface between boot loaders and 32-bit operating systems on x86 PC platforms, which attempts to solve the traditional problem that every single operating system tends to come with its own boot loader or set of boot loaders which are completely incompatible with boot loaders written for any other operating system. The MultiBoot standard allows any MultiBoot-compliant operating system to be loaded from any MultiBoot-supporting boot loader. MultiBoot is also designed to provide advanced features needed by many modern operating systems, such as direct 32-bit protected-mode startup, and support for boot modules, which are arbitrary files loaded by the boot loader into physical memory along with the kernel and passed to the kernel on startup. These boot modules may be dynamically loadable device drivers, application program executables, files on an initial file system, or anything else the OS may need before it has full device access. The MultiBoot standard is already supported by several boot loaders and operating systems, and is gradually becoming more widespread. For details on the MultiBoot standard see Section 10.14.12.
The MultiBoot standard is separate from and largely independent of the OSKit. However, if MultiBoot is used, the toolkit can leverage it to provide a powerful, flexible, and extremely convenient method of booting custom operating systems that use the OSKit. The toolkit provides startup code which allows MultiBoot-compliant OS kernels to be built easily, and which handles the details of finding and managing physical memory on startup, interpreting the command line passed by the boot loader, finding and using boot modules, etc. If you use the OSKit's MultiBoot startup support, your kernel automatically inherits a complete, full-featured 32-bit protected-mode startup environment and the ability to use various existing boot loaders, without being constrained by the limitations of traditional OS-specific boot loaders.