Forum
The forum module allows visitors to create new threads and reply to existing threads. The thread creator can also mark a specific reply as the "Answer" to help others quickly find the correct solution to a problem.
Adding the Forum to your Page
The forum has 2 modes Topics and Threads. When creating a new forum you will typically create a root page that will contain the Forum module in Topics mode and under the root Forum page will be the individual topic pages. Here is an example structure:

In this example we have our main forum page with 5 topic pages. Each topic page can have new threads created, an example here is the Page Editing topic which has a single thread. Please note: You do not create the individual threads in the CMS editor, that is done by the logged in user on the Topic page.
When you have created your forum page structure you need to add the Forum module to the root Forum page, this you need to set the Display Mode to Topics as shown below:
For each topic page you need to insert the Forum module again, this time setting the Display Mode to Threads. So in the example forum page structure above you would create 5 instances of the Forum module that have a Display Mode set to Threads.
Viewing the Forum
It is important that you approve all the Topic pages before you try to view your forum. When you view your forum page it will list all your Forum topics and will look something like this:

As you can see the 5 Topic pages are displayed together with their author, number of threads and posts information. The Topic page for "Page Editing" contains a single post:

When clicking a thread title a visitor can post replies and the thread creator can mark replies as "Answer".