The secret to simple selling is itself a simple secret: sell what people want to buy. How do you find out what people want to buy? Well, one answer is to ask them? Not a bad answer, but it has two problems: 1. People may not know what they want. 2. People may not be willing to tell you. There is another alternative: get the facts, rather than the opinions, since even the first-hand opinions are questionable. Find out what people are actually buying. What lots of people are buying, many other people will also want to buy. These other people are your market. A specific application of this principle... [...]