The American Marketing Association has defined Marketing as
"the activity, set of institutions, and processes for creating, communicating, delivering, and exchanging offerings that have value for customers, clients, partners, and society at large.“
Marketing is used to create the customer, to keep the customer and to satisfy the customer.
With the customer as the focus of its activities, it can be concluded that Marketing is one of the premier components of Business Management
source - wikipedia.org
It is always about your customer, his/her needs, desires, likes but also dislikes. Understand that and respect that. Only after you know your customer, you can start doing proper marketing.