Someone once told me that selling is the art of closing the deal.
This definition of selling encapsulates the heart of the matter, because selling is first and foremost a transaction between the seller and the prospective buyer or buyers.
If you're interested in improving your selling skills, you'll find that there are supposedly many kinds of selling that you should use or should avoid, such as high-pressure selling, persuasive selling, no-pressure selling, targeted selling, etc., but all of them amount to the same thing in the end; selling is the art of persuading the consumer that buying the product or service will benefit him or her.
Whatever product or service you're selling, then, you need to focus your selling efforts on communicating the benefits of your product or service to the consumer. The benefits may be tangible or intangible, but unless the individual consumer is convinced that he or she will personally experience the benefits, your product or service won't sell.
Think about it. Why do women smear color on their eyelids? Did anyone in the entire world ever actually need a hula hoop? That's the art of selling.