Posted 24 May 2010 - 03:40 PM
It looks like the video is asking you to change directories ( the cd command). After you type "cd cs", you need to press enter, not tab, as that will tell the operating system to execute that command. As a side note, you may want to be sure that the folder named 'cs' exists on your computer. If not, you can create a new folder with that name by typing "md cs" and pressing enter.
Hope this helps.