Marketing is the science and art of exploring, creating, and delivering value to satisfy the needs of a target market at a profit.  Marketing identifies unfulfilled needs and desires. It defines, measures and quantifies the size of the identified market and the profit potential. It pinpoints which segments the company is capable of serving best and it designs and promotes the appropriate products and services.

Marketing is often performed by a department within the organization. This is both good and bad. It’s good because it unites a group of trained people who focus on the marketing task. It’s bad because marketing activities should not be carried out in a single department but they should be manifest in all the activities of the organization.

In my 11th edition of Marketing Management, I describe the most important concepts of marketing in the first chapter.  They are: segmentation, targeting, positioning, needs, wants, demand, offerings, brands, value and satisfaction, exchange, transactions, relationships and networks, marketing channels, supply chain, competition, the marketing environment, and marketing programs.  These terms make up the working vocabulary of the marketing professional.

Marketing’s key processes are: (1) opportunity identification, (2) new product development, (3) customer attraction, (4) customer retention and loyalty building, and (5) order fulfillment.  A company that handles all of these processes well will normally enjoy success.  But when a company fails at any one of these processes, it will not survive.

Reference by Kotler