B2B or B-to-B stands for Business to Business and is a business model where you sell your products or services directly to another business. Business-to-business refers to business that is conducted between companies, rather than between a company and an individual consumer. Business-to-business stands in contrast to business-to-consumer (B2C).
Business-to-business models are common in the world of large corporations and are common place in the manufacturing and telecom world. Foxconn is one of Apple's oldest and larger suppliers of cellular phone components. Apple holds a B2B relationship with Foxconn.
Another example of a B2B relationship would be in the automobile manufacturing sector. United States car manufacturer, Ford, purchases the majority of their airbags from a company called Autoliv out of Stockholm, Sweden. Autoliv does not sell direct to consumers and individuals. Autoliv has a B2B relationship with Ford.