Multi-factor authentication is a type of authentication that requires multiple pieces of evidence to validate a user’s identity. It typically involves up to three factors – something the user knows (like a password or PIN), something the user has (such as a security token or cellphone), and something the user is (a biometric characteristic, like a fingerprint). For a user to be granted access, they must successfully present these factors. Additionally, multi-factor authentication can also be used to secure online transactions, such as online banking or online shopping. It is increasingly becoming the industry standard for online security, as it is much more difficult for an unauthorized user to gain access to an account with MFA in place.