Economists since the times of Adam Smith (1723-1790), looking at non-specific pre-modern societies as examples, have used the inefficiency of barter to explain the emergence of money, of "the" economy, and hence of the discipline of economics itself.[3] However, ethnographic studies have shown that no present or past society has used barter without any other medium of exchange or measurement, nor have anthropologists found evidence that money emerged from barter, instead finding that gift-giving (credit extended on a personal basis with an inter-personal balance maintained over the long term) was the most usual means of exchange of goods and services.[4]
Within the week, Simmons gave notice to her employer. By then, she’d been pining to leave for eight months and had diligently saved for the occasion. Her plan now was to barter her financial services with other women for one year. That would be enough time, she figured, to get the altruism out of her system, but not so much that she’d go broke. She would use $10,000 in savings to pay her cellphone bill and to parcel out $35 in emergency spending each week if and when bartering fell through on the basic necessities. That money would also help pay for most of the rent at the Dovercourt and Queen apartment she shared with her boyfriend, Matt, who was in the midst of changing careers. Everything else—food, clothing, haircuts, fitness, entertainment and transportation around the city—she would acquire through barter. Simmons figured she’d need to barter with 300 women to make it work. She gave the project a catchy name, Barter Babes, and started organizing a launch party. 

Even before visiting the Marquesas, I had heard from men who had touched at the group on former voyages some revolting stories in connection with these savages; and fresh in my remembrance was the adventure of the master of the Katherine, who only a few months previous, imprudently venturing into this bay in an armed boat for the purpose of barter, was seized by the natives, carried back a little distance into their valley, and was only saved from a cruel death by the intervention of a young girl, who facilitated his escape by night along the beach to Nukuheva. 

To try a time bank, search online for one in your local area using How time banks are managed varies according to the region, so it is important (and often mandatory) to attend an initial meeting that explains the general rules of your local chapter. Once you do this, you’re ready to start trading away. Your services and contacts are identified through the local time bank website.
No academics I talked to were aware of any evidence that barter was actually the precursor to money, despite the story’s prevalence in economics textbooks and the public’s consciousness. Some argue that no one ever believed barter was real to begin with—the idea was a crude model used to simplify the context of modern economic systems, not a real theory about past ones.