"I am very familiar with the various methods that are used to authenticate users. They include something you know, something you have, and something you are. Something you know is one of the most common authentication methods, and examples include asking the user for a PIN, password, or answer to a security question. In other cases, companies use authenticating devices like ID cards and cell phones to authenticate their employees; these devices are considered something you have. And then there's something you are, which includes things like a signature, fingerprint, or voice password. This type of authentication is usually the hardest to fake. At the last company I worked for, we required two-factor authentication where employees had to put in their password and then enter in a code that was sent to their cell phone in order to access the network."