An invention is something devised by human effort that didn't exist before. Inventions are by and large either responses to specific needs or products of the inventor's desire to do something more quickly or efficiently. Inventions rarely appear out of the blue. Inventors will often seek to adapt an older design, using a new material or configuration to suit a slightly different need. Think of all the different types of cups there are: glass ones, paper ones, plastic ones, teacups with handles, "sippy" cups, thermal mugs, and so on. Each of these was designed to meet a real or perceived need, shortcoming, or failure of the cups that came before it. And keep in mind that none of these cups has replaced the others; they merely continue to live side by side in cupboards everywhere.

At least in industrialized countries, it is more frequently want than need that drives the process of invention. Andrew, the boy inventor featured in this video segment, wants to automate the task of folding the newspapers he delivers on his paper route. The machine he devises does some of the work for him, though it still requires exertion on his part: He has to place the newspaper on the top shelf, turn the crank that makes the first fold, slide the piece of wood that makes the second fold, and slip a rubber band over the folded paper.

Though the video segment doesn't show Andrew's engineering design process, he probably spent a lot of time thinking about and discussing his idea with others. He may have also gotten some help from a skilled woodworker who could safely and neatly cut the curved grooves in the plywood that guide the newspaper-folding crank. Real-world inventors, product designers, and engineers typically go even further than just visualizing and drawing their plans and ideas; they develop initial models called prototypes that inform decisions about how the product will ultimately look and function.