Sync vs Backup ?

[Kenworth]

Hello all...
Could someone explain the actual difference between sync and backup in ITunes for my IPAD 2?
What is it I actually want to do?
I have I Cloud backup on in settings on the IPAD.

Thanks.......Ken

 

[scifan5764]

When you sync your device with iTunes on your computer, you can transfer items from the iTunes library on your computer to your device. This is much faster than downloading the items from the cloud.
An iTunes backup makes a complete record of what is on your device at the time you make the update. If you backup a device that has iTunes content that is not already in your iTunes library, it will transfer that content to your iTunes library as part of the backup procedure.

Sync your iPhone, iPad, or iPod touch with iTunes using USB - Apple Support

iTunes - Syncing & Transferring Content - Apple Support

How to back up your devices using iCloud or iTunes - Apple Support