A prosumer is a person who consumes and produces media. It is derived from "prosumption", a dot-com era business term meaning "production by consumers". These terms were coined by American futurist Alvin Toffler, and were widely used by many technology writers of the time.
"Prosumer" is also a trade term, used from a business perspective, for high-end electronic devices (such as digital cameras), meaning a price point between "professional" and "consumer" devices.
This blurring of the roles of consumers and producers has its origins in the cooperative self-help movements that sprang up during various economic crises e.g. the Great Depression in the 1930s.
Marshall McLuhan and Barrington Nevitt suggested in their 1972 book Take Today, (p. 4) that with electric technology, the consumer would become a producer. In the 1980 book, The Third Wave, futurologist Alvin Toffler coined the term "prosumer" when he predicted that the role of producers and consumers would begin to blur and merge (even though he described it in his book Future Shock from 1970). Toffler envisioned a highly saturated marketplace as mass production of standardized products began to satisfy basic consumer demands. To continue growing profit, businesses would initiate a process of mass customization, that is the mass production of highly customized products.
However, to reach a high degree of customization, consumers would have to take part in the production process especially in specifying design requirements. In a sense, this is merely an extension or broadening of the kind of relationship that many affluent clients have had with professionals like architects for many decades. However, in many cases architectural clients are not the only or even primary end-consumers, a distinction touched upon in the H+ Magazine essay 'Prosumption Architecture: The Decentralization of Architectural Agency as an Economic Imperative'.