hi all, i really need a hand with this. i've been using an external HDD for time machine for backing up my Mac and so far so good. however, i've got 2 other external HDD's: one is a 2TB drive and the other is a 1TB drive. i want to back them up, but each one has different files. how can i back them up without losing any files? i want to make one of them the main drive and the other one i want to make the 'back up' drive. are there any tools i can use to do this? thanks for any help! edit: one issue is both are current formatted in NTFS so i'll need to convert one of them to a format the Mac can read and write to as well as allowing a Win machine to read and write to them. which format should i use?