When you are using Windows Explorer - the file management program that opens when you double-click on 'My Computer' and the like - you can move to the parent folder by clicking the back-space key.By 'parent folder' I mean the folder that contains the one you are looking at. In the following image we see that the 'parent folder' of Adobe is Program Files.
Another way to achieve the same thing is to press the F4 key followed by the up arrow, and then Return.
Note for Vista users: using the Backspace key in Vista mimics the use in web browsers, that is, it takes you to the previous folder you looked at. To go to the parent directory using Vista, hold down Alt and press the Up cursor.
