Short for "business to business." Encompasses anything involved in aiding the interaction of one business with another. This is a very popular software market currently.

The severe misconception that is very non-Everything. The idea that somehow, businesses who conduct ecommerce with other businesses on the web follow some other set of rules than business to consumer (B2C).

The only slightly more enlightened concept includes B2B2C.

Whatever.

Some major B2B Companies: Ariba, Commerce One, Verticalnet, i2 ... by even eBay is starting a B2B exchange

To follow up on Stephan's comment: I really don't see the use for something like this. Businesses follow the same rules that consumers do in terms of purchasing (though they may purchase more). B2C is even more ludicrous -- it's e-commerce under an even more annoying buzzword name!