using two or more independent methods of authentication. Individuals need to authenticate using factors from at least two categories: something the user knows, something the user has, and something the user is. Knowledge factors are the most common type of security, but they are also the most vulnerable because the information is easier to share or steal. Authentication examples of something the user knows include passwords, PIN (or personal identification numbers), and answers to supposedly secret questions (such as “Where were you born?” or “The name of your first grade teacher”). Something the user has – also called possession factors – have been the foundation of security for centuries; the most basic version is a key, which opens a lock. Possession factors are more complex now, but the premise is the same. Authentication examples of possession factors include Google Authenticator (an app on your phone), SMS text message with a code, soft token (also called software token), hard token (also called hardware token), and security badge. A biometric verification (or something the user is) is a way to identify a person using their unique biological traits. Examples of biometric verification include fingerprint, palmprint, voice, retina and iris patterns, signature, and DNA. Reading level: 13.6 (in Word)