What is iCloud Backup?
iCloud backup lets users to back up the settings and data on their iOS devices (iPhone, iPad , etc) running iOS 5 or later. Data backed up includes photos and videos in the Camera Roll, device settings, app data, messages (iMessage, SMS, and MMS), ringtones, and Visual Voicemails. Backup are created and saved in the cloud whenever your device is locked and connected to WiFi and power backup. If you happen to lost all your data on your Apple device by chance, then you can restore all the data from the iCloud backup if your device was synced to iCloud.
If your iCloud backup storage is running out and you want more space, then you can either buy more space or clear out the existing storage by deleting some data. Now you know what is iCloud backup, what is backs up and how you can have more storage on your iCloud backup.
For more details on what is icloud backup and how to create : www.icloudlogins.net/icloud-backup/