As Orlove noted, barter may occur in commercial economies, usually during periods of monetary crisis. During such a crisis, currency may be in short supply, or highly devalued through hyperinflation. In such cases, money ceases to be the universal medium of exchange or standard of value. Money may be in such short supply that it becomes an item of barter itself rather than the means of exchange. Barter may also occur when people cannot afford to keep money (as when hyperinflation quickly devalues it).[15]
When two people each have items the other wants, both people can determine the values of the items and provide the amount that results in an optimal allocation of resources. Therefore, if an individual has 20 pounds of rice that he values at $10, he can exchange it with another individual who needs rice and who has something that the individual wants that's valued at $10. A person can also exchange an item for something that the individual does not need because there is a ready market to dispose of that item.
An alternate currency, denominated in labour time, would prevent profit taking by middlemen; all goods exchanged would be priced only in terms of the amount of labour that went into them as expressed in the maxim 'Cost the limit of price'. It became the basis of exchanges in London, and in America, where the idea was implemented at the New Harmony communal settlement by Josiah Warren in 1826, and in his Cincinnati 'Time store' in 1827. Warren ideas were adopted by other Owenites and currency reformers, even though the labour exchanges were relatively short lived.[20]
However, this isn’t always possible. For instance, you may have a $150 digital music player and want a small refrigerator worth $100. In this case, if both parties are certain of what they want and understand the difference in value, there should be no barterer’s remorse. Alternatively, you can ask for the mini-fridge plus $50 to make the trade – the worst anyone can say is “no.”
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.

Some businesses that may not directly barter with customers may swap goods or services through membership-based trading exchanges such as ITEX or International Monetary Systems (IMS). By joining a trading network (which often charges fees), members can trade with other members for barter "dollars." Each transaction is subject to a minimal fee; the exchange facilitates the swap and manages the tax components of bartering such as issuing 1099-B forms to participating members. You may find a nearby exchange through the International Reciprocal Trade Association (IRTA) Membership Directory. Before you sign up and pay for a membership, however, make sure that members offer the types of goods and services you need. Otherwise, you may find yourself with barter money or credit that you cannot use.
Bartering allows individuals to trade items that they already have but are not using for items that they need while keeping their cash on hand for expenses that cannot be paid through bartering such as a mortgage, medical bills and utilities. Bartering can also have a psychological benefit because it can create a deeper personal relationship between trading partners than a typical monetized transaction. Bartering can also help people build professional networks and market their businesses.

Identify your resources. What items do you have that you could easily part with? Use a critical eye to go through your home, and consider possessions you may have in storage or that another family member or friend is currently using. If you would prefer to offer services, honestly assess what you could provide for others that they would otherwise pay a professional to do. It could be a skill or a talent or hobby such as photography. 
A barter system is an old method of exchange. Th is system has been used for centuries and long before money was invented. People exchanged services and goods for other services and goods in return. Today, bartering has made a comeback using techniques that are more sophisticated to aid in trading; for instance, the Internet. In ancient times, this system involved people in the same area, however today bartering is global. The value of bartering items can be negotiated with the other party. Bartering doesn't involve money which is one of the advantages. You can buy items by exchanging an item you have but no longer want or need. Generally, trading in this manner is done through Online auctions and swap markets. 

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.[13]
This sort of scenario was so undesirable that societies must have created money to facilitate trade, argues Smith. Aristotle had similar ideas, and they’re by now a fixture in just about every introductory economics textbook. “In simple, early economies, people engaged in barter,” reads one. (“The American Indian with a pony to dispose of had to wait until he met another Indian who wanted a pony and at the same time was able and willing to give for it a blanket or other commodity that he himself desired,” read an earlier one.)
Another advantage of bartering is that you do not have to part with material items. Instead, you can offer a service in exchange for an item. For instance, if your friend has a skateboard that you want and their bicycle needs work, if you are good at fixing things, you can offer to fix their bike in exchange for the skateboard. With bartering two parties can get something they want or need from each other without having to spend any money.
Corporate barter focuses on larger transactions, which is different from a traditional, retail oriented barter exchange. Corporate barter exchanges typically use media and advertising as leverage for their larger transactions. It entails the use of a currency unit called a "trade-credit". The trade-credit must not only be known and guaranteed, but also be valued in an amount the media and advertising could have been purchased for had the "client" bought it themselves (contract to eliminate ambiguity and risk).[citation needed]
Since the 1830s, barter in some western market economies has been aided by exchanges which use alternative currencies based on the labour theory of value, and which are intended to prevent profit-taking by intermediaries. Examples include the Owenite socialists, the Cincinnati Time store, and more recently[when?] Ithaca HOURS (time banking) and the LETS system.
The man who arguably founded modern economic theory, the 18th-century Scottish philosopher Adam Smith, popularized the idea that barter was a precursor to money. In The Wealth of Nations, he describes an imaginary scenario in which a baker living before the invention of money wanted a butcher’s meat but had nothing the butcher wanted.“No exchange can, in this case, be made between them,” Smith wrote.
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]
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