DOS does not supports Multi-Threading..
yes!
They have just released new version which indeed does support it.
Multitasking is the execution of 2 or more programs at one time. Multithreading "threads" may be a stand-alone task. Video can be a thread and audio as another single program or application so it can be executed as two or more "threads" of instruction. Processors must support multithreading (processing) abilities of hardware to run two programs at once.
There is no any software for MSDOS shell as MSDOS is itself a system software.
Actually, hyperthreading is Intel's name for its implementation of simultaneous multithreading.
check
Simultaneous multithreading was first researched in 1968 as part of IBM's ACS-360 project.
Start=>Run=>msdos
It uses both techniques.
8
Microsoft Disc Operating System
Gwang-Myung Kim has written: 'Architectural support for multithreading on a 4-way multiprocessor' -- subject(s): Parallel processing (Electronic computers), Multiprocessors