A consumer is a person or a group who intends to order, orders, or uses purchased goods, products, or services primarily for personal, social, family, household and similar needs, not directly related to entrepreneurial or business activities.
“Consumers, by definition, include us all," President John F. Kennedy offered his definition to the United States Congress on March 15, 1962. This speech became the basis for the creation of World Consumer Rights Day, now celebrated on March 15. In his speech, JFK outlined the integral responsibility to consumers from their respective governments to help exercise consumers' rights, including: 
- The right to safety: To be protected against the marketing of goods which are hazardous to health or life.
- The right to be informed: To be protected against fraudulent, deceitful, or grossly misleading information, advertising, labeling, or other practices, and to be given the facts he needs to make an informed choice.
- The right to choose: To be assured, wherever possible, access to a variety of products and services at competitive prices; and in those industries in which competition is not workable and Government regulation is substituted, an assurance of satisfactory quality and service at fair prices.
- The right to seek redressal : Consumers have the right to seek redressal against unfair trade practices and exploitation. If any damage is done to a consumer, he has the right to get compensation depending on the degree of damage. 
- The right to represent : Thus, the Act has enabled us as consumers to have the right to represent in the consumer courts. 
In an economy, a consumer buys goods or services primarily for consumption and not for resale or for commercial purposes. Consumers pay some amount of money (or equivalent) for something - goods or services - which they (or their families ) then consume (use up). As such, consumers play a vital role in the economic system of a capitalist system  and form a fundamental part of any economy.    Without consumer demand, producers would lack one of the key motivations to produce: to sell to consumers. The consumer also forms one end of the chain of distribution.
Recently[ when?] in marketing, instead of marketers generating broad demographic profiles and Fisio-graphic profiles of market segments, marketers have started to engage in personalized marketing, permission marketing, and mass customization to target potential consumers. 
Largely due to the rise of the Internet, consumers are shifting more and more[ quantify] towards becoming prosumers, consumers who are also producers (often of information and media on the social web) - they influence the products created (e.g. by customization, crowdfunding or publishing their preferences), actively participate in the production process, or use interactive products.   
The law primarily uses a notion of the consumer in relation to consumer protection laws, and the definition of consumer is often restricted to living persons (not corporations or businesses) and excludes commercial users.  A typical legal rationale for protecting the consumer is based on the notion of policing market failures and inefficiencies, such as inequalities of bargaining power between a consumer and a business.  As all potential voters are also consumers, consumer protection has a clear political significance.
Concern over the interests of consumers has spawned consumer activism, where organized activists do research, education and advocacy to improve the offer of products and services. Consumer education has been incorporated into some school curricula. [ citation needed] There are also various non-profit publications, such as Which?, Consumer Reports and Choice magazine, dedicated to assist in consumer education and decision making.
In India, the Consumer Protection Act 1986 differentiates the consumption of a commodity or service for personal use or to earn a livelihood. Only consumers are protected per this act and any person, entity or organization purchasing a commodity for commercial reasons are exempted from any benefits of this act. 
- "Special message to Congress on protecting consumer interest, 15 March 1962". John F Kennedy Presidential Library and Museum.
Schor, Juliet B. (2014).
Born to Buy: The Commercialized Child and the New Consumer Culture. Simon and Schuster.
Kids and teens are now the epicenter of American consumer culture.
Henderson, Fred (2014) .
Capitalism and the Consumer. Routledge Library Editions: Consumer Behaviour. Abingdon, Oxfordshire: Routledge. p. 38.
9781317565109. Retrieved 14 October 2021.
[...] the completion of the producing process by the use and consumption which carries the goods-production into human life itself [...].
- Consumers play a pivotal part in economics, which Krugman and Wells define as the study of production, distribution and consumption. Krugman, Paul; Wells, Robin (2012). Economics (3 ed.). Worth Publishers. p. 2. ISBN 9781464128738.
- Note for example Alexander Chayanov's analysis of peasant economies, and compare consumer goods in the Soviet Union. At a fundamental level, economic agents (individuals, groups and states) work/hunt/gather/trade so that they and their dependants can eat.
- Bren, Paulina; Neuburger, Mary, eds. (2012). Communism Unwrapped: Consumption in Cold War Eastern Europe. Oxford: Oxford University Press. ISBN 9780199827664. Retrieved 14 October 2021.
- Cross, Robert G. (1997). Revenue management: hard-core tactics for market domination. Broadway Books. pp. 66–71. ISBN 978-0-553-06734-7.
- Gunelius, Susan (3 July 2010). "The Shift from Consumers to PROsumers". Forbes. Retrieved 2 July 2016.
- Scammell, Margaret. "Citizen Consumers: towards a new marketing of politics?" (PDF). p. 6. Retrieved 2 July 2016.
- Blättel-Mink, Birgit; Hellmann, Kai-Uwe (27 October 2009). Prosumer Revisited. ISBN 9783531169354. Retrieved 2 July 2016.
- Krohn, Lauren (1995). Consumer protection and the law: a dictionary. ABC-CLIO. ISBN 978-0-87436-749-2.
- "An Institutional Analysis of Consumer Law". Vanderbilt Journal of Transnational Law. Archived from the original on March 2, 2007. Retrieved 2007-01-29.
- L. Gayle Royer (1980). "The Value of Consumer Education in Increasing Effective Consumer Performance: Theory and Research". Advances in Consumer Research. 07: 203-206. Retrieved 24 January 2020.
"Consumer vs Customer". Consumerdaddy.com. Archived from
the original on 2010-04-06. Retrieved 2010-03-10.
The consumer protection act 1986 of India, is a little more generous with the word 'Consumer'. According to this law, a consumer is not only a person who uses the product for domestic personal use, but also one who uses the product to earn his daily livelihood.
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