How do you backup using Time machine?
Do I have to have an external hard drive?
Is there any way to backup using without a external hard dirve?
MacBook Pro, Mac OS X (10.7.5)
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You can back up using Time Machine to a second partition of your internal disk, but that's useless, so you should buy an external disk to make Time Machine backups.
See > http://support.apple.com/kb/HT1427 Also, I recommend you to make a clone with Carbon Copy Cloner, too