###Course Outcomes Add log in, logout, and sign-up functionality to 2 existing web applications. By the end of the course, you will know how to manage user access to your web application. This course builds off knowledge from the Learn Rails course.
###Why learn authentication? Most applications out there require you to sign up. As a user, you can sign up for a service, log in, and log out when you're done. As a creator of a web app, you probably don't want every user to have access to every single part of the app—like customer details, security information, raw data—so you'll want to restrict access. Rails: Authentication teaches you how to do this within a Rails application.