I wanted to buy an external hard drive to back up my stuff that i want to delete off my computer. Im probably will never need to go back in time to retrieve a file its just a security option incase my drive crashes or something. My questions are: 1) Would it be worth it for me? 2)Can i still drag files onto the hard drive and delete them from the time machine part? 3)Is it worth it to have a time machine taking up a half of the drive if i don;t use it often?