Backing up your iPhone in a regular basic is a good practice to avoid sudden hardware fail, data corruption or software conflicts. On the other hand it’s a must to take a backup before hacking the iPhone so that if things go wrong you can at least restore from your old backup file. With a complete backup, you can backup your iPhone sound settings, widget settings, network settings, text messages, notes, call history, emails, along with customization preferences.
Do note that iPhone backup and iPhone sync are two different terms and tasks. Many people take data syncing as data backup and face problems once they really need to restore an old backup. The basic difference is that data sync may restore all your files while data backup will restore all your files along with all previous settings.

Here is what you need to know about iPhone Data Sync and Backup:
1. You can use iTunes to sync content on your computer such as music, podcasts, videos, ringtones1, photos, email account settings, contacts, calendars, and bookmarks with your iPhone or iPod touch.
2. Syncing makes sure this content is the same on your iPhone or iPod touch and computer.
3. You can also use iTunes to create a backup of settings and certain other information on your iPhone or iPod touch to use in case you want to restore the software on your iPhone or iPod touch or transfer this information to a different device.
4. Backup file includes information such as mail settings, text messages, notes, call history, contact favorites, sound settings, widget settings, certain network settings, and other preferences.
You can follow a special tutorial made by Apple to know more on how to create a backup, restore from a backup and deleting a backup.
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