FrontEndUsers (FEU) and CustomContent (CC) are modules that allow for user login/authentication and checking user status on the frontend of a website. FEU manages users, groups, and user properties while CC provides smarty access to the login status of visitors. These modules have an easy installation process and setting up users involves creating properties, groups, and user accounts. Templates can utilize the $ccuser smarty object to control content based on login status and retrieve user property values. The modules also have APIs to extend their functionality and be integrated into other modules.