DOS and UNIX are computer operating systems that give your computer the capability to execute files and run programs. They are both text-based; however, there are some variances between them. For instance, UNIX has a GUI, but DOS does not. GUI is a graphical user interface that allows your computer to interact with electronic devices by clicking an icon as an alternative to using command prompts.
UNIX has further security than DOS, so it is more for server use, while DOS is geared towards home use. UNIX is case sensitive, but DOS is not, and example would be in UNIX a folder with Edward.exe and edward.exe would be considered two distinct files, and in DOS, it would be considered the same file. Also, Unix uses // and DOS uses \\ in their directory structure. Just remember DOS is for personal use and UNIX for server use.