I've just bought a Mac mini to replace a windows laptop that has come to the end of its days. I have an external hard drive that I have back ups of my digital photos on, along with files I want to take across to my Mac. Whilst the drive is recognised and I can view or copy the files from it to my Mac I cannot write to it or delete files stored on it. It is I believe a 2tb drive, which is probably less than a quarter full, so I want to make use of it. From looking on this website and other internet sites I guess it's currently formatted just for PC, so will need reformatting to enable write as well as read only access from my Mac. If I'm understanding it correctly I have two options to make it useable as a backup and not lose the data on it. option one copy all the files on it onto my macs internal hard drive. Format my external to suit my Mac. Copy/move files back onto external. option two copy all the files onto my macs internal. Format external to suit Mac. Leave files on internal. Use external as a time machine, which, if I'm understanding it correctlay, will give the advantage of backing up the whole system and not just my files. My question is (a) is my understanding correct and (b) which is the best option?