ChimeIn uses the "course" as the basic enclosure for questions. However, ChimeIn can be used in many non-course scenarios. You can make up a course designator - for example, "TEST1001" - to contain your questions.
For things like conferences, your participants likely won't have X500 accounts. For that reason, we recommend marking the course as "public." That'll allow users to access the course without authenticating, though they'll still need to know the right address.
You can reveal the "public" address by clicking on the word "public" in your course. Your users can visit that address with their laptop or smartphone. You can also create a shorturl to point your users to that address.
For users participating via text message, there's no need to pre-register the phone number. You'll just need to provide them with the phone number (612-41-chime) and the question number to include in their responses.