Mac OS X 10.6: Important application files to back up
Most applications use special files to hold user data or preferences. Before you erase or reformat your hard disk or update your system software, make sure you back up these important files or your entire home folder. To back up files, drag them from their original location to another disk, or burn them on a CD or DVD. Time Machine can also help you back up your files. For more information about Time Machine, choose Help > Mac Help in the Finder and search for Time Machine.
The table below shows the locations of the data files for commonly used applications. The tilde (~) character indicates the name of your home folder, which is the same as your user name. (For example, if your user name is Anna, your home folder is named anna.) If you can’t back up your entire home folder, back up these data files.
~/Documents and ~/Desktop
Mail data and settings
iTunes data and settings
iPhoto data and settings
Address Book data and settings
iCal data and settings
Safari data and settings
Keychain data and settings
Applications not made by Apple may store user data in different locations. For more information, check the documentation that came with your application.
If you’ve moved application data, such as your iTunes or iPhoto library, from its original location, make sure to also back up that data.