Two-factor authentication (also known as 2FA or 2-Step Verification) is a technology patented in 1984 that provides identification of users by means of the combination of two different components. These components may be something that the user knows, something that the user possesses or something that is inseparable from the user. A good example from everyday life is the withdrawing of money from a cash machine. Only the correct combination of a bank card (something that the user possesses) and a PIN (personal identification number, something that the user knows) allows the transaction to be carried out. 2FA is ineffective against modern threats, like ATM skimming, phishing, and malware etc. Two-factor authentication is a type of multi-factor authentication.