Customer, also known as a purchaser, buyer or a client is a person who is currently using any product or service of any firm or organization. In other words, a person who is referred to a current buyer, purchaser or a client who buys product from any vendor, seller or supplier. This relationship builds with the help of purchasing and selling of goods and services. On the other side, any viewer who views the advertisement of any product or service is also known as a customer for that particular product or service.
Customer is a word that is derived from habit. It is actually derived from the habit of buying same product from the same supplier. Varieties of terms are linked with this single word i.e. "customer". Customer services, customer orientation, customer relationship and many others. In every context, aim is to target the customers, give them what they want and make them happy and satisfied from your product or service. In this perspective, the main role is of the seller who is selling the product or service. If product is sold at right time and to the right customer, relationship builds stronger and stronger and thus it helps in increasing the number of customers too. There is a misconception that a person who buys is only the customer. Whereas as mentioned earlier, the one who view the product or service is also the customer because he views it and will further do the publicity and this will eventually increase the potential of the goods and services.
References
Ken Blanchard, Jim Ballard, Fred Finch (2005), "Customer mania!: it’s never too late to build a customer-focused company", HarperCollins Publishers Limited, pg 194