Stories are a very powerful tool as a designer. We can use it for methods in order to gain creativity, proof of concept, and future thinking, but also as a tool to sell our product to a company.
The Narration in the Design Process
The Exploratory play for example, is just one of many narration techniques, that can be used in a design process. It describes how we can come up with new ideas by just rearranging and recombining parts of stories, in order to gain new outcomes which can lead to new views, perspectives and therefore new ideas for a design problem.
Another method is the filtering, which allows us to proof our concept against a specific scenario where the product is meant to be settled in. It describes the way of placing your concept into a scenario in order to proof if it sounds reasonably right or not. If not we have to iterate in our idea finding. Filtering can also be a nice way to get other people to know your ideas.
A way to gain creativity for new projects or concepts is to look back in history to get an inspirational view of the past. What has been done and why. A good example for this is the the methodology of media archeology where artists and designers, hackers and people of the do-it yourself community take a look to the past in order to understand the evolution of nowadays media technology. This acknowledgement leads to different outcomes, for example circuit hacking or contemporary media art.

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Narration as a selling technique
Narration is also a nice tool to sell, whether it is just an idea or a finished product. Although, the content of the story may be important, the way how and whom we tell the stories to shall not be forgotten. This is where the four levels of decision influences by Christoph Loch are developed, in order to understand a companies organisation structure. This can help to get to know how and where we as designers have to place our arguments that result in agreement. This influencing and manipulating can give us the opportunity to place our design the most efficient in a companies structure.
Manipulation through storytelling
Nowadays, especially with the rise of modern media, stories have a big impact to people. People try to spread information to influence people, often for their own purpose. We as designers can use this technique, in order to sell our products and designs to companies and finally to the user. But we have to take care that do not oversell our idea. Marketing is important but useless if there is no reasonably good product behind it.