Use the command prompt to implement entered commands, Command prompt is the most common implementation of batch files, perform advanced administrative functions, and to explore and resolve certain types of cases and Windows.
Well basically what he said, but they're multiple things to do on it such as installing new Windows onto your USB or DvD to make it bootable, backup your PC, Hide your IP and even do heaps of cool commands that make your PC go crazy! But overall, it's something you should start researching about because it's quite interesting