Despite the fact that there are millions of Apple users nowadays, it seems that the difference between the Apple ID and iCloud ID accounts and passwords is still unclear. So, we thought we'd briefly explain what each of these is and then look to see if they differ.
Apple ID
An Apple ID is a username for everything one can do with Apple. It is an account, where only Apple users can log in. The Apple ID is a way of getting your information on Apple's database so that you can identify yourself on your MacBook, iPhone or iPad.
The Apple ID can be used to log into various Apple products, such as iMessage, iCloud, the iTunes Store and the Apple Store. It allows Apple users to shop products such as games, music, and application form the Apple Store.
To make sure your Apple ID is protected from fraud, you should set up two-factor authentication. It serves as an extra layer of security, designed to ensure that you're the only person who can access your account, even if someone knows your password. The two-factor authentication dramatically improves the security of your Apple ID and all the personal information you store with Apple because it requires both a passcode (or a password) and biometric authentication.
iCloud ID
iCloud is an account that you set up that gives you access to tools built around synchronizing and accessing your data on multiple devices. There are many ways this comes in handy on a computer or an iOS device for synchronizing your address book and calendars, files, photos, and videos.
If you share Apple products like your iPad and MacBook with members of your family, you can create a discreet iCloud ID for each member. That way, all users would have their own iCloud experience for email, messages, calendar, photos, etc., which means that your personal information will not be accessed from everyone who uses the same devices.
Difference
The Apple ID and the iCloud ID are two different accounts, but the confusion comes that they can be accessed with the same email ID. As mentioned earlier, the Apple ID is used for signing into the iCloud. When you log into the iCloud, the email address and password are your Apple ID. The iCloud can be thought of as an extra service added on top of the Apple ID login. And as they are so tightly linked, they can often be considered the same account.
Source: justaskgemalto