Two-step verification, also referred to as multi-factor authentication, is an online security measure to further help protect your account and other personal information. It's a second layer of defence, after your password.
The use of verification codes makes two-step verification more secure. To help prevent unauthorized access to your account, you'll need to confirm your identity with a verification code. This will only occur when necessary, e.g. you're in a different city.
Sign in to your user ID or account as usual. Only when we need to confirm your identity, you'll be asked for a verification code.
Your verification code is sent to a phone number that you chose. Simply enter your verification code.
Set up challenge questions as an alternate authentication method so that you don't have to enter in a verification code at sign in when prompted.