Reader

The Reader permission level allows users to view content from your workspace.  Please note, that if the Administrator of a workspace sets the Workspace Security setting of the workspace to allow anyone to view the site, then the site will be available to users who are not logged in.

This applies to all pages, files, and comments where the user has the "Reader" permission level.  For pages and files, the Reader permission can be set in the users list or in the Folder or Page Security of the space.

Tip: To secure content of your workspace to make it "Read only" set the permission level of users to be "Reader".  This way they'll only be able to download and view content, and no changes will be made by their account.