A one-time password (OTP) is type of password that is valid for a single use. A password is generated after a regular interval of time and cannot be used again.
One-time password is a sequence of random numbers generated by smartphone applications or devices like key tokens. OTP is used together with normal password for multi-factor authentication (authentication of password+α). Even if your log-in password is leaked, others cannot log in to your accounts if you possess a device that generates one-time password. For this reason, OTP is effective in avoiding unauthorized login.
One-time password provided by SKUID can be used for the smartphone application, Google Authenticator.