Since the 1830s, direct barter in western market economies has been aided by exchanges which frequently utilize alternative currencies based on the labor theory of value, and designed to prevent profit taking by intermediators. Examples include the Owenite socialists, the Cincinnati Time store, and more recently Ithaca HOURS (Time banking) and the LETS system.
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If you've ever swapped one of your toys with a friend in return for one of their toys, you have bartered. Bartering is trading services or goods with another person when there is no money involved. This type of exchange was relied upon by early civilizations. There are even cultures within modern society who still rely on this type of exchange. Bartering has been around for a very long time, however, it's not necessarily something that an economy or society has relied solely on.
Other anthropologists have questioned whether barter is typically between "total" strangers, a form of barter known as "silent trade". Silent trade, also called silent barter, dumb barter ("dumb" here used in its old meaning of "mute"), or depot trade, is a method by which traders who cannot speak each other's language can trade without talking. However, Benjamin Orlove has shown that while barter occurs through "silent trade" (between strangers), it also occurs in commercial markets as well. "Because barter is a difficult way of conducting trade, it will occur only where there are strong institutional constraints on the use of money or where the barter symbolically denotes a special social relationship and is used in well-defined conditions. To sum up, multipurpose money in markets is like lubrication for machines - necessary for the most efficient function, but not necessary for the existence of the market itself."