from the 14th century onwards. Its evolving linguistic meanings reflect the early history of the growing cash economy and the evolution of commercial trade. Nowadays the meaning of "price" is obvious and self-evident, and it is assumed that prices are all one of a kind. This is with respect to how money has become used ubiquitously for nearly all transactions. But in fact there are many different kinds of prices, some of which are actually charged, and some of which are only 'notional prices'. Although a particular price may not refer to any real transaction, it can nevertheless influence economic behavior, as people have become accustomed to valuing and calculating exchange-value in terms of prices, using money (see real prices and ideal prices). Commodification In the first chapters of Das Kapital, Marx traces out a brief logical summary of the development of the forms of trade, beginning with barter and simple exchange, and ending with a capitalistically produced commodity. This sketch of the process of "marketisation" shows that the commodity form is not fixed once and for all, but in fact undergoes a development as trade becomes more sophisticated, with the end result being that a commodity's exchange-value can be expressed simply in a (notional) quantity of money (a money price). However, the transformation of a labor-product into a commodity (its "marketing") is in reality not a simple process, but has many technical and social preconditions. These often include: the existence of a reliable supply of a product, or at least a surplus or surplus product; the existence of a social need for it (a market demand) that must be met through trade, or at any event cannot be met otherwise; the legally sanctioned assertion of private ownership rights to the commodity and the right to trade it; the enforcement of these rights, so that ownership is secure; the transferability of these private rights from one owner to another; the (physical) transferability of the commodity itself, i.e. the ability to store, package, preserve and transport it from one owner to another; the imposition of exclusivity of access to the commodity; the possibility of the owner to use or consume the commodity privately; guarantees about the quality and safety of the commodity, and possibly a guarantee of replacement or service, should it fail to function as intended; the ability to produce the commodity at a cost and sale-price sufficient to yield