What is multifactor authentication (MFA)?

Multifactor authentication (MFA) is defined as a security mechanism that requires two or more forms of verification to access a resource. This method enhances security by requiring users to provide multiple pieces of evidence to verify their identity. Typically, these forms of verification fall into three categories: something you know (like a password), something you have (like a smartphone or a security token), and something you are (like a fingerprint or other biometric data).

By implementing MFA, organizations significantly reduce the risk of unauthorized access, even if one verification method is compromised. For example, even if a password is stolen, an attacker would still need the secondary verification method (such as a code sent to a mobile device) to gain access. This layered approach to security makes it much more difficult for potential intruders to breach systems or access sensitive information.

The other options, while related to security, do not accurately capture the essence of MFA. A single form of verification does not constitute MFA, and methods focused solely on securing physical locations or eliminating passwords do not encompass the broader definition of MFA.