Space requirements for Time Machine?

I have recently bought an iMac (last week) and awaiting my update to Leopard. One of the novelties that interests me most about Leopard is the Time Machine, but I was wondering how much disk space it would require on my external drive.
I know this depends on the data I need to back up. Both my internal and external drive are 500 Gb. I have for some 100 Gb worth of data, pictures and applications on my internal drive, and for some 350 Gb of data on the external drive.
Does Time Machine backup everything, including the installed applications, or can one indicate which files should and should not be backed up.
Thanks for your response.
Amenhotep III

...but I was wondering how much disk space it would require on my external drive.
You'll need enough space on the external to contain the initial backup, subsequent hourly backups will be incremental as you create/ make changes to files/ folder. One of the nice features with TM is that you can set its preferences to exclude files and folder, making the backups much smaller in size.
I have for some 100 Gb worth of data, pictures and applications on my internal drive, and for some 350 Gb of data on the external drive.
The external will be of sufficient size for TM backup. When TM finally fills the external it can then over-write the older backups if you wish (or you can attach another disk to keep every backup it ever made, not necessary for most I think).

Similar Messages

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    Sorry about the poorly worded question.

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    Tim Whelan2 wrote:
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    2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Note the SMART status of the drive in DU's status area. If it does not say "Verified" then the drive is failing or has failed and will need replacing. SMART info will not be reported on external drives. Otherwise, click on the Partition tab in the DU main window.
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    Visit The XLab FAQs and read the FAQ on Backup and Restore.
    Hopefully the next vacation you go on you will prepare for more thoroughly in advance. And, don't swear at the computer - it's a machine and only does what you tell it to do. If you need to swear at something look in the mirror!

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