Great question!

Thread Starters are conversational nudges dropped into your group messenger on Threads based on your group settings. The nudges can be light and fun or deep and informative based on your group chat settings

Your group will receive a notification when a new prompt has arrived in your group chat. To answer a prompt, simply click the “answer” button to share your reply within the prompt thread. You’ll receive a notification when members of your group answer prompts in the thread, and then view the group's answers and chat about the discoveries you make about one another.

To check out the types of Thread Starters on Threads, click here.