There is no any software for MSDOS shell as MSDOS is itself a system software.
What is MS DOS Shell
Yes, it was the original Disk Operating System popularized by Microsoft as MS-DOS.
MS-DOS 6.22 was the last stand-alone version of MS-DOS. Some believed that MS-DOS 7.0 was the last version of MS-DOS since Windows 95 reported MS-DOS as MS-DOS 7.0. However, this was just a shell in Windows and not a stand-alone version of MS-DOS.
tui because a gui is a graphical user interface which is anything that lets you interact with your PC
MS-DOS was initially released in 1981 for the Intel 8086 and 8088 based processors. There are no software requirements for MS-DOS as it is a stand-alone operating system. MS-DOS is compatible with x86 systems.
MS-DOS ended with Windows NT. It used file command.com to interpret all DOS commands. Win 2000, XP, Vista use a DOS Shell which emulates DOS but is not really DOS.
Yes. It is a disk operating system.
DOS is an operating system, so it's leaning towards system software.
Shell..
It is the command interpreter: command.com
"Shell Script is series of command written in plain text file. Shell script is just like batch file in MS-DOS but have more power than the MS-DOS batch file."