How to Setup 2-Factor Authentication on Apple ID for Extra Security
This guide will walk through setting up two-factor authentication for an Apple ID. Two-factor authentication requires that whenever a user is logging in to an Apple ID from a new untrusted device, not only must the proper password be entered but a secondary security ID code must be entered as well, which is typically delivered to a trusted device or through text message to a trusted phone number. This offers an additional security layer and significantly enhances security for Apple ID and iCloud account use, because essentially it means that even if someone were to know the password for an Apple ID, unless they had access to a pre-determined trusted device, they would not be able to log in to that account.
Not all users will want to use two-factor authentication for Apple ID and iCloud access, but for the security conscious it can be a good idea as it offers added protection to the account and related data. Consider that an Apple ID typically contains data about a users address book and contacts, notes, iCloud mail, credit card information, iCloud keychain, iCloud backups, iCloud photos, purchase history, and much more, and you can quickly see why the Apple ID is something to protect well, which two-factor authentication does.