The other DOS, which comes only with the XP, 2000 and NT operating systems, is cmd.exe. Usually cmd.exe is better than other commands because it is easier to use, has more commands, and in some ways resembles the bash shell in Linux and other Unix-type operating systems. For example, you can repeat a command by using the up arrow until you back up to the desired command. Unlike bash, however, your DOS command history is erased whenever you shut down cmd.exe.
I think the op's referring to "denial of service" apps, not "disk operating system"
OSCP - Offensive Security Certified Professional : Failed my first attempt at the OSCP exam
