A storyboard or scene book is a graphic version of a script or a visualization of a concept or idea. Storyboarding in UX Design is a tool, which can help you visually predict and explore a user's experience with a product. It's a more like to reflect on your product, like it's a movie in term of how people would use it. This would help you to understand how people would flow through the interaction over time, giving you a clear sense of how to create a strong narrative with focus on Human-Centered Design approach.