The Internal Revenue Service (IRS) considers bartering a form of revenue and something that must be reported as taxable income. Under U.S. generally accepted accounting principles, or GAAP, businesses are expected to estimate the fair market value of their bartered goods or services. This is done by referring to past cash transactions of similar goods or services and using that historical revenue as a reportable value. When it is not possible to accurately calculate the value, most bartered goods are reported based on their carrying value.
Some entrepreneurs are already taking the principles of swapping—use everything and anything you already have to survive—to create another offshoot system, one that turns a hefty profit. Called the sharing economy, it is perhaps best exemplified by Airbnb, a service that enables people to rent out their apartments like hotels. Other sites let you turn your driveway into a parking space, your car into a taxi and your tools into a rental service. Forbes estimates revenue flowing through the U.S. sharing economy will hit $3.5 billion by the end of 2013, and maybe more. It’s worth mentioning that some business associations and government members are terrified of this rise: like most alternative economies, it’s largely tax-free.
mid-15c., apparently from Old French barater "to barter, cheat, deceive, haggle" (also, "to have sexual intercourse"), 12c., of uncertain origin, perhaps from a Celtic language (cf. Irish brath "treachery"). Connection between "trading" and "cheating" exists in several languages. Related: Bartered; bartering. The noun is first recorded 1590s, from the verb.
Anthropologists have argued, in contrast, "that when something resembling barter does occur in stateless societies it is almost always between strangers, people who would otherwise be enemies."[6] Barter occurred between strangers, not fellow villagers, and hence cannot be used to naturalisticly explain the origin of money without the state. Since most people engaged in trade knew each other, exchange was fostered through the extension of credit.[4][7] Marcel Mauss, author of 'The Gift', argued that the first economic contracts were to not act in one's economic self-interest, and that before money, exchange was fostered through the processes of reciprocity and redistribution, not barter.[8] Everyday exchange relations in such societies are characterized by generalized reciprocity, or a non-calculative familial "communism" where each takes according to their needs, and gives as they have.[9]

When barter has appeared, it wasn’t as part of a purely barter economy, and money didn’t emerge from it—rather, it emerged from money. After Rome fell, for instance, Europeans used barter as a substitute for the Roman currency people had gotten used to. “In most of the cases we know about, [barter] takes place between people who are familiar with the use of money, but for one reason or another, don’t have a lot of it around,” explains David Graeber, an anthropology professor at the London School of Economics.