When you track a thread, it means that you will be sent a notification when someone else replies to that tracked that. Tracking a thread You would track a thread when you want to keep up with everything being said.
Note: You automatically track your own threads when you post them.
Step 1: Find a Thread
Find a thread you are interested in on the forum. Click on that thread so that you are at the top of the first page.
Step 2: Track The Thread
At the top right of the header, there should be a "Track Thread" button. Clicking on this will make you track the thread and it will now say "Untrack thread". Clicking it again will untrack the thread.