An OTP (One-time passwords) is a password given to the user for one login session only, which must be used within a certain amount of time. OTPs are sent from tech support to people who need help registering or logging into a website. They are also used as a second means of logical access authentication, very often if a person logs in from a new computer using two-factor authentication (2FA).
As soon as the one-time password (OTP) is entered, it is no longer valid. Also called a time-based one-time password (TOTP), they are used by physical authentication devices such as smart card or a USB authentication token.
