Before users can access APEX applications, they have to log in. This is typically done by providing a user name and corresponding password. If the credentials match, then a user becomes authenticated and can proceed to use the application. If not, then the user will be prompted to try again. Too many invalid attempts, and the account may become disabled, requiring an administrator to intervene.
The mapping of a user repository to an APEX application is called an authentication scheme. Each application can have multiple authentication schemes embedded within it, but only one can be set as the current authentication ...