Your OPTIMAL Guest Calendar can be set to either a Public mode or a Private mode.
In Public mode, anyone you have given the public calendar link (http://parentingtime.net/calendar/) to can view your Guest Calendar by going to that URL and entering your Account ID.
If you've created any events in the calendar or marked blocks of time, they'll be able to see the events and time periods, and they'll also be able to hover over them and see any notes you may have entered or left for them.
In Private mode, no one can view your Guest Calendar- it is completely hidden from everyone. If someone tries to view it, they'll get a polite message telling them the calendar is not available for viewing at this time. You can test this by setting your Guest Calendar to Private mode and then trying to view it.
By default, your OPTIMAL Calendar is set to Private mode so it can't be viewed by anyone.
To change the Calendar privacy setting, go to your Personal Settings screen and click the Calendar tab. Follow the instructions on the page to set the Calendar to either Public or Private.