Barter-based economies are one of the earliest, predating monetary systems and even recorded history. People can successfully use barter in many almost any field. Informally, people often participate in barter and other reciprocal systems without really ever thinking about it as such -- for example, providing web design or tech support for a farmer or baker and receiving vegetables or baked goods in return. Strictly Internet-based exchanges are common as well, for example exchanging content creation for research.

In trade, barter (derived from baretor[1]) is a system of exchange where participants in a transaction directly exchange goods or services for other goods or services without using a medium of exchange, such as money.[2] Economists distinguish barter from gift economies in many ways; barter, for example, features immediate reciprocal exchange, not delayed in time. Barter usually takes place on a bilateral basis, but may be multilateral (i.e., mediated through a trade exchange). In most developed countries, barter usually only exists parallel to monetary systems to a very limited extent. Market actors use barter as a replacement for money as the method of exchange in times of monetary crisis, such as when currency becomes unstable (e.g., hyperinflation or a deflationary spiral) or simply unavailable for conducting commerce.
It was the fifth lasagna that did it. Three months into the project, Simmons had signed up over 80 Barter Babes, and every time she bartered her financial services, she seemed to get a lasagna in return. She was trying to shove yet another five-pound pasta dish into her freezer when the tears started to flow. “I don’t need another lasagna!” she yelled at her boyfriend. “I need a haircut! I need a bicycle!” She was overwhelmed with doubts about her bartering experiment: I’m so ridiculous. What the hell was I thinking? This whole thing is never going to work. Trades weren’t happening at the frequency she had anticipated, and Simmons was feeling depressed. She couldn’t afford a dye job at a salon, and she had started gaining weight. She’d gone from ballin’ to having $200 in her joint account.