Add Yahoo as a preferred source to see more of our stories on Google. What's a verification code, and why are they so important? Six-digit verification codes are a form of two-factor authentication, a ...

Google is changing the way you confirm if contacts are legit. The company has begun rolling out a QR code to verify that the person you're communicating with is, in fact, who they say they are, ...

, a process that helps keep your important online accounts secure. For example, you might get a text message or email with a six-digit code that you must enter when you log into your bank account.