In recent years, barter has enjoyed a resurgence as a means of countering economic insecurity, unemployment and worker exploitation. The nature of modern-day work, the pervasiveness of the Internet and the rise of social networking have all contributed to its spread. Other examples of alternative economic systems include gift economies, sharing economies and time banks.
In his analysis of barter between coastal and inland villages in the Trobriand Islands, Keith Hart highlighted the difference between highly ceremonial gift exchange between community leaders, and the barter that occurs between individual households. The haggling that takes place between strangers is possible because of the larger temporary political order established by the gift exchanges of leaders. From this he concludes that barter is "an atomized interaction predicated upon the presence of society" (i.e. that social order established by gift exchange), and not typical between complete strangers.
Bartering is based on a simple concept: Two individuals negotiate to determine the relative value of their goods and services and offer them to one another in an even exchange. It is the oldest form of commerce, dating back to at time before hard currency even existed. (Learn more about how bartering evolved, read The History of Money: From Barter To Banknotes.)
It’s hard to answer that without actually seeing a modern gift economy in action. Luckily, modern gift economies actually do exist. On a small scale, they exist among friends, who might lend each other a vacuum or a cup of flour. There’s even an example of a gift economy on a much larger scale, albeit one that’s not always in operation: The Rainbow Gathering, an annual festival in which about 10,000 people gather for a month in the woods (it rotates among various national forests around the country each year) and agree not to bring any money. Groups of attendees set up “kitchens,” in which they prepare and serve food for thousands of people every day, all for free. Classical economists might guess that people would take advantage of such a system, but, sure enough, everyone is fed, and the people who don’t cook play music, set up trails, teach classes, gather firewood, and perform in plays, among other things.