After Apple took some heat for it’s less than stringent password reset policies, Apple is now securing your Apple IDs with two factor authentication, which is a delight for iCloud users. In the case of apple, how two factor authentication would work is that your iPhone, iPad, or iPod Touch would work as your second authentication device. While logging in, one of your iOS devices will provide you with a code that you must enter along with your password. This method is much more secure than just using a single password, and other vendors are providing the same type of support. Google and Microsoft both offer two factor authentication in order to get into their websites.
Currently it is reported that there is about a 3 day waiting period to enable this feature. Trust me on this one it is well worth the wait as a layered security approach is one of the most adequate ways to protect yourself from unauthorized access.