Resources has two types of files: public and private. The public folder is meant for any files you want to be generally accessible on your website for all users. Private files, however, are meant only for specific constituents. Use this folder for files that need to be displayed on your site only to certain users, such as board members. This section is kept completely separate from public files and can only be accessed if a user is logged in. Use a private collection, and you can specify exactly which users, in a role or group, are allowed to view the file.