Mockup Prototype Definition. A prototype often confused with a wireframe is a middle to high fidelity representation of the final product which simulates user interface interaction. Wireframes mockups and prototypes are common terms used by product teams.

A mockup is a prototype if it provides at least part of the functionality of a system and enables testing of a design. Mockups come before prototypes which are simulations of what a live page will be. A prototype often confused with a wireframe is a middle to high fidelity representation of the final product which simulates user interface interaction.
A mockup is a prototype if it provides at least part of the functionality of a system and enables testing of a design.
A mockup is a prototype if it provides at least part of the functionality of a system and enables testing of a design. You can test it present it to clients for approval etc. Unlike the previous two a prototype is clickable and thus allows the user to experience content and interactions in the interface. In fact they are only needed to demonstrate the design and are full size images of your future website.