Have you ever logged into an online account and then received a text message to confirm it was you actually logging in? It’s a common experience nowadays, especially with financial accounts, but increasingly with many kinds of online accounts that have sensitive information.
This type of security is called two-factor authentication, because you need two kinds of verification to prove that it’s really you – not some bad guy – accessing the account. Two-factor authentication is one of the most widespread technologies used to secure your account, but at least one observer suggests that the tech has not been studied enough to know its weaknesses.