Nice job! Now when you fill in the signup form and submit it, the data is sent to the Rails app via a POST request. The request hits the User controller's
create action. The
create action saves the data, creates a new session, and redirects to the albums page.
How is a new session created? Sessions are stored as key/value pairs. In the
create action, the line
session[:user_id] = @user.id
creates a new session by taking the value
@user.id and assigning it to the key