Two-step verification for Apple ID - Apple Support

Two-step verification for Apple ID If you can't use two-factor authentication with your account, for example if your device uses iOS 8 or OS X Yosemite or earlier, you can keep your Apple ID secure with two-step verification instead. Is two-step verification the same as two-factor authentication? What is two-step verification for Apple ID? How does it work? Do I still need to remember any security