In Moodle is teacher the right default role when you want everyone in the site to be able to have full write privileges?

Please answer this if you can, and then retag it. Thanks

To clarify the question, what is the minimum role you can assign as a default for a site that will let the participants add material (and activities) to the site? Do they need to be Course Creator, or is Teacher enough. Or is there a lower role that would still give them rights to add content and activities?