title: Can one controller point to different models?
body: <p>i am currently developing a login and registration system,
  The login system(its own controller, model and view) includes function such as:
  validate, if_uname_exists, if_email_exists, etc</p>
  
  <p>registration system(its own controller, model and view) includes functions:
  register,send_activation,send_email, etc</p>
  
  <p>However i have a need to make a user controller, which has the username as a data member, and i need to call on functions such as is_admin(), update_profile(). So my doubt is, should those functions be included a user model, or rather can i have them in another model, for example: login model or maybe a profile model?</p>
  
  <p>Are there any best practices to follow on the same?
  Thanks alot</p>