A prototype can simulate the final design through functionality and interactivity, and can take the form of paper sketches, linked wireframes, or a pre-alpha version. Prototypes can fall on a spectrum from "Lo-Fi" to "Hi-Fi" depending on how close they are to resembling the final product. Prototypes help communicate and test ideas early in the design process.

5.  Functionality
 Interactivity
 Simulates the final design
Can be:
 Paper
 Linked wireframes
 Pre-alpha version

7. Lo-Fi Hi-Fi

8. Lo-Fi Hi-Fi