iCloud account

The Apple ID email address and password you use to turn on and use iCloud services and to access the web applications on iCloud.com.

You can find your iCloud account information in these places:

On your iOS device: Tap Settings > iCloud.
On your Mac: Choose Apple menu > System Preferences (in the top-left corner of your screen), then click iCloud.
On a Windows computer: If you have Windows 8, move the pointer to the upper-right corner of the screen to show the Charms bar, click the Search charm, then click iCloud Control Panel on the left. If you have Windows 7 or Windows Vista, choose Start menu > All Programs > iCloud > iCloud.

Note: If you upgrade your account to iCloud Drive, syncing may not work in all cases, depending on which versions of OS X and iOS you have installed. See this Apple Support article for more information.