B2B, trade of products or services, between a manufacturer and a wholesale company often consists of big transactions as opposed to B2C which often consists of small transactions. 

The manufacturer is the supplier and the wholesale company is the customer in this case.

Being a supplier in this kind of B2B chain could be quite complex since there could be raw materials involved where these are put together in a production chain. Refined and if it is a producing organisation, the raw material is the product that somehow will be shipped to the customer who in his turn will refine or trade the product one step further.

The customer is in his turn often a supplier but could as well be performing directly against end customers.

Trading documents or information between the organisation is often sent through fax or some kind of integration message between procurement systems or directly between ERP systems.