This document discusses authentication and authorization architecture in browser applications. It covers authenticating and authorizing clients to protect them from outsiders and each other. It discusses using cookies versus tokens to maintain state and different authentication providers like Passport. It also discusses authorizing by role, resource, or custom and setting up API routes and restricting access by object or post-query filtering. The client side uses Angular to handle login and check authorization status before accessing resources. Templates can show/hide elements based on authorization.