Marketing is all activities conducted to prepare for sales. Sales is all activities required to close the deal. Shipping and customer satisfaction would be included in sales to avoid the customer from reversing or unclosing the deal.
Thus Marketing can be categorized as a branch of business as well as a social science. We buy goods (thus becoming the buyer/consumer) from a vendor (or producer/seller), creating a transaction. In the past, marketing involved traveling salesmen, while in modern times, marketing is more likely to involve television, the internet, and other forms of media bombardment.
Peter Drucker’s definition of marketing is: “Marketing and innovation are the two chief functions of business. You get paid for creating a customer, which is marketing. And you get paid for creating a new dimension of performance, which is innovation. Everything else is a cost center.”