A:Answer As formatted, this drive is ready for PC. MAC can READ files from the drive, but it will be read-only. MAC could not WRITE files to the filesystem as formatted.
To use this drive with BOTH MAC & PC, reformat it as exFAT on your MAC. Then, both your MAC and PC can read and write to the filesystem.
If you only want to use this drive on MAC, format it as Journaled on you MAC.
Time Machine on MAC can use the drive if it is exFAT, but you have to do a few more commands so that Time Machine can see it. Google: timemachine exfat sparsebundle to find the command.
We are PC users in our house. but using a new Macbook Pro for work. Took a while to figure out why all of my usb drives were read-only on my Mac. Lots of new things to learn. Good luck!