When creating a trip on Travelstormer, you have the following global privacy options. You can change this setting later as well.
1. Fully Private - Make all pages in your trip private to the people whose email addresses you enter.
2. Semi-Private - Allow anyone with a single unique link to view the trip and join the group if they wish.
Fully Private
Under this setting, the people listed in the Trip Participants section are the only ones who can see your trip and contribute.
When you invite someone under this setting, they get a 'temporary' account until they sign up and create a proper one themselves.
With this status they can view the trip as well as contribute to the decision-making features. You may find in some cases these users can stay in this 'temporary' state, since you may only need them to contribute to decision-making and nothing else.
Once they sign-up they have full access to contribute as a trip member.
Note: This setting is overruled by Brainstorm privacy. ie. If you have a private trip, and a public brainstorm, the brainstorm will remain public, which the rest of the trip remains private. Read more about Brainstorm privacy here.
Semi Private
Under this setting, we'll give you a "Public Link". This means the trip is publicly accessible, but only for those who have this specific link.
From this link, a person will have read-only access to the trip with the option to join and contribute. When these users attempt to contribute, we present them log in or sign up options before continuing.
Once they join the group it puts them into full trip member status, and into the trip participants section.
You might use this option if you want to send the link to a large number of people via your own method, this could be Facebook, Twitter etc.
The downfall of this method is that unless these people join the group from the link described above, they won't get trip activity sent to them, they'll have to keep coming back to see what's happening.