Customer segmentation is dividing your current, former, or potential customers into groups, or segments, according to various criteria that are significant to you. These criteria may be gender, age range, city, and country, as well as simple demographic variables as well as that have more economic meaning for you.
For example, you can segment your customers based on criteria such as the products and services that the customer is interested in, the channel through which the customer reached you, the last time or how often they contacted you, and how much they shopped from you, how many times they opened your campaign mails, or for what reason they stopped shopping from you. You can separate easily.