With itunes, it is similar, but its not realtime backup.
It remains unchanged, so even if you screw something up, like delete messages you dont want to lose, you can go back and restore your phone from that backup. Icloud backup basically bundles a ton of content on your device and packs it up into its own little file and saves it on icloud. There is also an option in that same list for icloud backup. All the things with the green slider turned on will sync in real time. The ability to sync content in real time for anything in the settings under settings>your name>icloud. You basically have two functions for icloud. You can easily backup most of your content to icloud.
