Mockup Vs Prototype. Unlike a wireframe a mockup looks more like a finished. It behaves and acts just like the final website app product so it is ideal to be used to test for potential app problems before moving into the development stage.
It is rather a graphic representation. You can test it present it to clients for approval etc. You might need to use a mockup tool.
The key difference between mockups and prototypes is that mockups are not interactive.
Also if you want to check out some great mockups you can go to dribbble. It behaves and acts just like the final website app product so it is ideal to be used to test for potential app problems before moving into the development stage. Mockup a kind of high fidelity static design diagram should demonstrate information frames and statically present content and functions. Unlike a wireframe a mockup looks more like a finished product or prototype but it is not interactive and not clickable.