You'll want a pair of drives for the Windows machine and a pair for the Apple. That's 4 drives total. Some folk think a single drive is backup. Sadly that's no backup according to your IT training. 1 copy is 1 copy. 2 copies is backup. Since this is backup, you need 3 copies to start. What's on the PCs and your 2 backup copies.
If your Apple has firewire I'd like to see firewire drives.
Bob
I have a MacBook that I use with both OS X and Win 7. I want an external drive to make backups but I do not know what to get. What type of external drive is fastest/most stable/easiest to use?
An USB 3 drive that I would connect directly into my computer?
An USB 3 drive that I would connect to my router? Physically this would be simpler to use but would it be much slower since my computer would communicate with my router through WiFi?
An external drive that connects to my router with an Ethernet cable?

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