• C2C (Consumer-to-Consumer). The scheme "consumer - to the consumer".
For example, OLX and ebay.com and similar, where any user, even if he is not an entrepreneur, can sell any thing or service.
• B2B (Business-to-Business). Business-to-business scheme.
This type of sales is more massive. Large batches of goods are sold to the dealer. He transfers the goods to small wholesale online stores that usually sell it to the consumer.
• B2C (Business-to-Consumer), "business-to-consumer".
This is a retail agreement between legal entities and individuals. Rent, purchase of coaching courses, payment in the online store.
• E2E (Exchange-to-Exchange), "exchange - exchanges".
In the Internet, this type is used for transactions between the sites or brokers to exchange goods and services between entrepreneurs. E2E can be considered as a form of B2B.
• G2C (Government-to-Citizens).
Payment for utilities, taxes, licenses, certifications and so on.
In response, citizens receive government information, at which point it ceases to be "e-commerce."