Synchronization is the process of updating information on different computers or devices so that all copies of your files contain the latest changes. For example, if you have calendars on more than one computer, you can synchronize them so that each computer has the latest information.

If you have a .Mac membership, you can synchronize your calendars across multiple computers via the Internet. To synchronize calendar information on your computer, mobile phone, Palm OS device, or iPod, use iSync (in your Applications folder).

Note: If you have iTunes 4.8 or later installed, you use iTunes, not iSync, to transfer contacts and calendars to your iPod.

By default, calendar syncing via .Mac is turned off in iCal preferences. To turn it on, choose iCal > Preferences, and in the General pane, select the "Synchronize my calendar with other computers using .Mac" checkbox.

For more information about syncing information across computers using .Mac, search Mac Help (in the Finder, choose Help > Mac Help).

For information about synchronizing calendars on other devices, open iSync (in your Applications folder) and then choose Help > iSync Help.