A prototype is an early, trial version of a product/service made to test and improve ideas before the final version is created. Prototype is a preliminary, often incomplete, version of a product, ...

Opinions expressed by Entrepreneur contributors are their own. Amazon Fire Phone, Google Glass, New Coke and Nintendo’s Virtual Boy: What do all these products have in common? They didn’t sell.

In this digital world, it may be hard for some to believe that there’s still a place for anything manual or physical—especially in the engineering realm. And, while it’s true that today’s technologies ...