The prototype is what you will develop so as to test your idea with the user. It needs to be cheap and quick to make. This connects directly to the real world. In business and industry. Imagine putting time and money into a final product that, when you test it, the users don't like or want. It is better to fail fast at the prototyping stage in order to progress to a design which will work well.
“They slow us down to speed us up. By taking the time to prototype our ideas, we avoid costly mistakes such as becoming too complex too early and sticking with a weak idea for too long.”
– Tim Brown
There are many methods for prototyping which include:
Cardboard prototyping is a valuable skill for students to learn in a school setting as it allows them to physically visualise their ideas and test them out in a low-cost and low-stakes way. Many industries, such as engineering, use cardboard prototyping to develop new ideas.
Storyboards are a useful tool in prototyping because they allow designers to visually organise ideas to show users a system or journey. It doesn't need to look perfect - stick figures and sketches are fine.