Current logged in user details

I am a student and new to mendix platform. I have some following questions regarding some app. How to get current logged in user details. username,password. i have seen something like this[%CurrentUser%]The GUID of the user currently logged in. what is GUID here ? how to get other details of the user using GUID. Is it possible to call microflow when user clicks sign-in button instead of homepage. Thanks
1 answers
  1. use $CurrentUser to access the user object and details.
    But why do you need the users username & password? that should only be used by the user to login, which is already possible using the default login page. not something you need to worry about.
  2. set a microflow as homepage