If you wish keep your Exposure site private you can enable a password to protect it in your Site Preferences. Once enable it will require anyone visiting your Exposure site to enter the password to enter. This applies to your Exposure URL (username.exposure.co) or if you have a custom domain enabled.
A password can be any string with no spaces but is limited to 20 characters.
This password protection only applies to your site and not individual stories. Those will still be accessible if a visitor has the exact URL. Once a visitors has entered the password they won't need to enter it again until they clear their browser history.
Once your Password is enabled you will see a "Password On" message in your menu to remind you. You can clear a password at anytime.
A visitors coming to site will see a minimal password form they will be required to fill out before they can access any further.
Site Passwords are managed from your Site Preferences and is a Pro and above Subscriber feature.