Booting a Linux install via external Hard Drive (rather USB Stick), is the process any different?

Booting a Linux install via external Hard Drive (rather USB Stick), is the
process any different?

I'm going to be installing Linux Mint onto a netbook, but I do not have a
spare USB key. I do however have an external USB hard drive that I use for
Time Machine backups on OSX.
I've partitioned an 8gb fat section with disk utility in OSX as the first
partition on the drive. Is it as simple as putting the distro's live CD's
ISO on the hard drive and then booting from it via the netbook? Or does
the fact that it's a HDD rather than a USB stick change what I need to do
to make it bootable.