OAuth is a publicly available way of logging into third party websites without having to use a password.
This can only be carried out if an individual has an account on a major website such as Google, Microsoft or Twitter for instance.
This is an open standard for authorisation and is designed as a way for users to allow websites or applications to access their information on other websites, without giving them the passwords.
The technology allows users to share information about their accounts with third party apps or websites.