Key Difference: The iTunes Account is linked with an Apple ID; both are dependent on each other. Apple ID is an account, used to log into various “i” stores. iTunes itself is a media player, where one needs an Apple ID to download various applications.

iTunes itself is a media player and media library application developed by Apple Inc. If anyone wants to download or purchase from the iTunes Store, they need to have an Apple account. It will be easier for the users to download unlimited files. An iTunes Store account is basically necessary because information about the user's library must first be sent namelessly to Apple's database.

Apple ID is an account, where only Apple users can log in. An Apple user can log into various products, such as iWork, iCloud, the iTunes Store, and the Apple Store. There is no need of different IDs for different products. Apple ID is available free-of-charge; only a valid email address and a password that is an alphanumeric case sensitive string of at least 8 characters are required.

In simple terms, an Apple ID is a username for everything one can do with Apple. Using an Apple ID one can shop the iTunes store, sign into iCloud, buy an app, use iMessage or many other such things. 

The Apple ID and iTunes account is basically one and the same thing. There is just a difference in name and nothing else. The iTunes Account is linked with the Apple ID. One needs an Apple ID to log into their iTunes Account. If one doesn’t have an Apple ID, he will need to create one before he can begin using the iTunes Store.

Since iTunes 7, purchased music can be copied from the iPod onto the computer. The computer must be certified by that iTunes account. iTunes at present lets up to 5 computers to be certified on one account. To de-authorize and register new computers subsequently, all accounts must be deleted, pursued by registering the live one. This can be done only once a year.

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