Investment has different meanings in finance and economics. Finance investment is putting money into something with the expectation of gain, that upon thorough analysis, has a high degree of security for the principal amount, as well as security of return, within an expected period of time. In contrast putting money into something with an expectation of gain without thorough analysis, without security of principal, and without security of return is speculation or gambling. As such, those shareholders who fail to thoroughly analyze their stock purchases, such as owners of mutual funds, could well be called speculators. Indeed, given the efficient market hypothesis, which implies that a thorough analysis of stock data is irrational, all rational shareholders are, by definition, not investors, but speculators.

Investment is related to saving or deferring consumption. Investment is involved in many areas of the economy, such as business management and finance whether for households, firms, or governments.

Peter Lynch (born (1944-01-19)January 19, 1944) is a Wall Street stock investor. He is currently a research consultant at Fidelity Investments. Lynch graduated from Boston College in 1965 and earned a Master of Business Administration from the Wharton School of the University of Pennsylvania in 1968.

Lynch was hired as an intern with Fidelity Investments in 1966 partly because he had been caddying for Fidelity's president (among others) at Brae Burn Country Club in Newton, Massachusetts. He initially covered the paper, chemical, and publishing industries, and when he returned after a two-year Army stint he was hired permanently in 1969. This time Lynch was charged with following the textiles, metals, mining, and chemicals industries, eventually becoming Fidelity's director of research from 1974 to 1977. In 1977, Lynch was named head of the then obscure Magellan Fund which had $18 million in assets. By the time Lynch resigned as a fund manager in 1990, the fund had grown to more than $14 billion in assets with more than 1,000 individual stock positions. From 1977 until 1990, the Magellan fund averaged a 29.2% return. Lynch's achieved dollar successes in a range of stocks including (by order of profit achieved - source is Beating the Street): Fannie Mae, Ford, Philip Morris, MCI, Volvo, General Electric, General Public Utilities, Student Loan Marketing, Kemper, and Lowes.

Ping Li (Chinese: 李平; pinyin: Lǐ Píng) is a Professor of Psychology, Linguistics, and Information Sciences and Technology at Pennsylvania State University. He specializes in language acquisition, focusing on bilingual language processing in East Asian languages and connectionist modeling. Li received a B.A. in Chinese linguistics from Peking University in 1983, an M.A. in theoretical linguistics from Peking University, a Ph.D. in psycholinguistics from Leiden University and the Max Planck Institute for Psycholinguistics in 1990, and completed post-doctoral fellowships at the Center for Research in Language at the University of California, San Diego and the McDonnell-Pew Center for Research in Cognitive Neuroscience in 1992. Li has been employed at the Chinese University of Hong Kong (1992–1996), the University of Richmond (1996–2006), and Pennsylvania State University (2008–present), and he has also served as a Visiting Associate Professor at Hong Kong University (2002–2003), an Adjunct Professor at the State Key Laboratory for Cognitive Neuroscience and Learning at Beijing Normal University (2000–present), as well as Program Director for the Perception, Action, and Cognition Program and the Cognitive Neuroscience Program at the National Science Foundation (2007–2009).

James Beeland Rogers, Jr. (born October 19, 1942) is an American investor and author. He is currently based in Singapore. Rogers is the Chairman of Rogers Holdings and Beeland Interests, Inc. He was the co-founder of the Quantum Fund with George Soros and creator of the Rogers International Commodities Index (RICI).

Rogers is an outspoken proponent of the free market, but he does not consider himself a member of any school of thought. Rogers acknowledged, however, that his views best fit the label of Austrian School of economics.

Rogers was born in Baltimore, Maryland and raised in Demopolis, Alabama. He started in business at the age of five by selling peanuts and by picking up empty bottles that fans left behind at baseball games. He got his first job on Wall Street, at Dominick & Dominick, after graduating with a bachelor's degree in History from Yale University in 1964. Rogers then acquired a second BA degree in Philosophy, Politics and Economics from Balliol College, Oxford University in 1966.