B2B vs B2C vs C2C vs C2B

B2B – business-to-business
B2B refers to businesses that are focused on selling products or services to other companies are called B2B, or business-to-business.
Example: Firms selling raw material to other firms, marketing companies

B2C – business-to-consumer
B2C is the type of commerce transaction in which businesses sell products or services to consumers.More recently, the term B2C refers to the online selling of products, or e-tailing, in which manufacturers or retailers sell their products to consumers over the Internet.
Example: Flipkart ,Amazon

C2C – consumer-to-consumer
C2C is a business model that facilitates the transaction of products or services between customers. An example of C2C would be the classifieds section of a newspaper, or an auction. In both of these cases, a customer, not a business, sells goods or services to another customer.
Example: Olx, Quikrr

C2B – consumer-to-business
C2B (consumer-to-business) model allows businesses to extract value from consumers – and vice versa. In the C2B model, businesses profit from the willingness of consumers to name their own price or contribute data or marketing to the company, while consumers profit from flexibility, direct payment, or free or reduced-price products and services.
Example: GoIbibo, Trivago, Paisabaazar.com