Revopoint Inspire – point cloud -> fusion -> mesh. What is a "fusion"?

This is probably a newbie question; I have searched for it but am not finding an answer. I’m using a Revopoint Inspire – a self-given Christmas gift. I’m using the accompanying Android app. After scanning, there is a Fusion option and subsequently a Mesh option. I understand that after scanning, it effectively has a point cloud, and I understand that a mesh describes the surface of an object. What does the intermediate Fusion part? What is it storing here?