is the buying and holding of shares
of stock on a stock market
by individuals and funds in anticipation of income from dividends
and capital gain[?]
as the value of the stock rises.
An investor may buy shares, that is ownership equity, of a company or bonds, that is debt of a company. Diversification both between debt and equity and between different companies is often recommended as is the practice of "buying low and selling high," should one be so wise and quick.  (http://www.yesyoucantimethemarket.com/)
To try to predict good stocks to invest in, two main schools of thought exist: technical analysis and fundamentals analysis.
- Yes, You Can Time the Market!, by Ben Stein (Author), Phil DeMuth (Author), John Wiley & Sons, 2003, hardcover, 240 pages, ISBN 0471430161
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