Hello anyone who reads this. Sorry if I sound desperate but I am right now. This is what happened: I heard about the "sudo- rm R " or something code, and I've been using it to delete my big files completely. I know it deletes the files completely, and saves space. I told my brother to use that to delete his stuff too, to save space. Then he began to delete all his files, from his user. (He and I have different user accounts, both as administrators). He apparently dragged all his files and downloads, and deleted them using that code. This happened: At first, there were no applications at all. The dock showed the applications icons with a question mark. The applications folder was completely empty. Then, I tried to see if restarting it was the solution. I know, stupid thing, but I wasn't thinking well. Now, the computer won't start up. It just gets to the white screen with the apple, begins to load for a few seconds, and then apparently it restars. It goes to the black screen again, and then to the white screen with the apple and so on... I have NO idea what happened, I am kinda new to Mac, but I fear I just f****d up my Mac and I am really scared. I have some important stuff there! What happened??? What can I do??? (It is a Black Macbook, I bought it last year) Please, HELP ME!