In general, to invest is to distribute money in the expectation of some benefit in the future – for example, investment in durable goods, in real estate by the service industry, in factories for manufacturing, in product development, and in research and development. However, this article focuses specifically on investment in financial assets.

In finance, the benefit from investment is called a return. The return may consist of a profit from the sale of property or an investment, or investment income including dividends, interests, rental income etc., or a combination of the two. The projected economic return is the appropriately discounted value of the future returns.

Investors generally expect higher returns from riskier investments. When we make a low risk investment, the return is also generally low.

Investors, particularly novices, are often advised to adopt a particular investment strategy and diversify their portfolio. Diversification has the statistical effect of reducing overall risk.