What is dual factor authentication?

Dual factor authentication is a type of security system that allows human beings to enter into protected networks over the internet. An example of authentication is a password. Because only you know your password, only you can log on to your myspace or retrieve cash from an atm. This is considered to be one "factor" of authentication. By using two factors, such as a password combined with, say, a verification text message sent to your mobile phone, security is significantly enhanced.

So, that's what dual factor authentication is!