B2B is also known as B to B which means business to business.
B2B is when a business transacts with another business such as a business relationship between a manufacturer and a wholesaler or a big wholesaler and a retailer. This kind of relationship occurs when a company needs materials needed in their manufacturing processes. For example, Apple Inc has B2B relationships with firms like Intel, Samsung and Micron technology.
B2B can be for products or even for services. For example, companies which produce heavy machinery for other manufacturing firms are offering B2B products. Bühler is one such example. And in B2B service, haulage and logistics counts as B2B service, for example Blackbuck, or Gati, or even Delhivery.
It is noteworthy that a firm can be both B2B and B2C. For example, Amazon does sales both to consumers and to businesses. Likewise, DHL is another business that caters to both businesses and consumers.