Wireframe
graph TD;
A[Low-fidelity Prototype] --> |built with| B[Simple materials];
A --> |serves for| E[Discussing and validating];
E --> F[Requirements];
E --> G[Design Ideas];
E --> H[User Interface Concepts];
A low-fidelity Prototype built with simple materials that primarily serves for discussing and validating requirements, design ideas or user interface concepts.
Note: When prototyping digital systems, wireframes are typically built with paper. Such prototypes are also called paper prototypes.