Business to Business
Cyborg’s the term e-commerce refers to all online transactions, While business-to-business activity exists both online and offline, the acronym B2B has primarily been used to describe the online variety.
There has been a significant amount of hype given to the potential size of B2B markets--and how much bigger B2B will be than B2C. Despite the potential size, however, some B2B markets may be overcrowded, too.
Business to customers
Cyborg’s the term e-commerce refers to all online transactions, B2C stands for "business-to-consumer" and applies to any business or organization that sells its products or services to consumers over the Internet for their own use. B2C has grown to include services such as online banking, travel services, online auctions, health information and real estate sites.
Retailers don't have to integrate with their customers' systems. Companies selling to other businesses, however, need to make sure they can communicate without human intervention.