What is multifactor authentication (MFA)?

Multifactor authentication (MFA) is defined as an authentication method that necessitates the use of two or more verification factors to gain access to a system or application. This method enhances security by requiring users to provide multiple forms of identification before allowing access, making it significantly more difficult for unauthorized individuals to succeed in gaining access, even if they have managed to acquire one of the verification factors, such as a password.

The essence of MFA lies in its use of varied types of authentication factors, which generally fall into three categories: something you know (like a password), something you have (such as a smartphone or hardware token), and something you are (biometric identifiers like fingerprints or facial features). By requiring users to confirm their identity using more than one of these categories, MFA creates layered security that increases overall protection against identity theft and unauthorized access.

Other methods mentioned, like a one-time password sent via SMS, biometric methods, or just a simple username and password combination, do not encompass the principle behind multifactor authentication fully. Instead, they may represent singular approaches to authentication that typically lack the multi-faceted verification that MFA aims to achieve.