[psmith2.0]

My friend and her roommate both have their own separate accounts set up on their 17" iMac. Each have their own e-mail, bookmarks, iTunes libraries, etc. At any one time, one or the other are logged into their account.

They do indeed have an external hard drive (I think it's a good 200-300GB if I remember) and I want them to start using Time Machine.

When one account is logged in and the other isn't, is that other, in the background maybe, being backed-up every hour two? Is Time Machine smart enough to "look inside" the Mac, to all user accounts, and do this?

Or is it only when you're logged in as that particular user?

And a second thing: will it create, on the hard drive, two backup accounts/folders, for each user? I want to be able to answer this for them, and get them (ASAP!) to hook the drive and start Time Machine (they've both got files that they really need to back up and can't afford to lose, considering their professions: documents, presentations, articles and reports, in addition to their personal music and photos).

If they connect the drive and enable Time Machine, will it back up each account as they're logged-in, and keep the two separate on the drive?

[kieran]

That's a good question. I haven't thought about that.

However, I don't know.

[kieran]

Apple support has said that everything on the drive gets backed up when Time Machine runs, so I don't think it matters if someone is logged in or not.

TM backs up the entire HD.