Apple ID is both your iTunes account and the login to your iCloud account. It’s essentially your one-stop shop for all things Apple. It contains your payment and shipping information for purchases from both the digital music, movie, and app stores, and physical products from Apple.com. It contains your personal information, passwords, and security, and it also stores all of your subscriptions and in-app purchases in the App Store.
Apple ID Accounts vs. iCloud Accounts – Understanding the Difference
Then where is all the confusion?
When Apple changed from a company that sold music via iTunes for playback on an iPod to a company that sold smartphones and tablets, it just didn't make sense to sign into these products with an "iTunes account" anymore. So the iTunes account was renamed the Apple ID.
The Apple ID is used across all of Apple’s products, from iPhone to iPad to Mac to Apple TV. If you have one of these devices, you’ve been prompted to sign in or create an Apple ID to use it. You don’t need more than one Apple ID. In fact, the experience is better if you use the same Apple ID across all of your devices. You can download apps to your iPad that you bought on your iPhone, and some apps will even let you download the Apple TV version.
