# Utilities Definition in Economics: Utility Explained

Published: 2026-04-19
Author: Warren Team
URL: https://www.heywarren.com/blog/utility-economics

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When economists say "utility" they don't mean an electric company. They mean the satisfaction or benefit a person gets from consuming a good, service, or experience. That single idea — utility — is the bedrock of demand theory, behavioral economics, expected value calculations, and ultimately every choice you make about what to buy, what to do, and what to skip.

The concept sounds soft. How do you measure happiness? Yet utility powers some of the hardest math in modern finance, from portfolio optimization to insurance pricing to the Nobel-winning work of Daniel Kahneman. Understanding the utilities definition economics uses lets you decode why people behave irrationally with money, why [diversification](/blog/what-is-diversification) matters, and why a $50 loss stings more than a $50 gain delights.

This guide walks you through utility from its 1870s origins to its modern role in behavioral finance. You'll learn cardinal versus ordinal utility, the equimarginal principle, indifference curves, expected utility theory, prospect theory, and how all of it shows up in your portfolio, your insurance policy, and your daily spending decisions. Warren — your AI financial advisor at heywarren.com — uses these same frameworks to give conflict-free guidance, so by the end you'll see your own choices through a sharper lens.

## Utilities Definition in Economics: The Core Concept

In economics, utility is a measure of the satisfaction, happiness, or benefit a person derives from consuming goods, services, or experiences. It is subjective, personal, and the engine that drives demand. Without utility, prices would have no anchor and consumer choice would be unintelligible.

Utility is not the same as price, cost, or even usefulness in the colloquial sense. A glass of water has enormous utility to a desert hiker and trivial utility to someone standing by a faucet. The same item delivers different utility depending on the consumer, the quantity already consumed, and the context. This subjectivity is a feature, not a bug — it explains why markets clear at all.

Economists treat utility as the mental currency consumers use to compare options. When you choose tacos over pizza, you've implicitly judged that the tacos deliver more utility for the price. Multiply that across billions of daily decisions and you get the structure of every market.

## Cardinal vs Ordinal Utility

Early economists imagined utility as a quantity you could measure in units called "utils." This is cardinal utility — the idea that a slice of pizza might give you exactly 12 utils and a beer 15. Modern economics largely abandoned this approach because nobody can actually measure happiness in absolute units.

Today economists use ordinal utility, which only requires that consumers rank their preferences. You don't need to say pizza gives 12 utils; you only need to say you prefer pizza to a salad and a salad to plain rice. Ordinal utility is weaker but more honest, and it turns out to be enough to derive demand curves, indifference curves, and most of consumer theory.

### Why Ordinal Won

Ordinal utility survived because it required fewer assumptions. Pareto and Hicks showed in the early 20th century that you could rebuild consumer theory using only rankings. The cardinal approach lingers in expected utility theory, where we still need numerical values to compute averages under uncertainty.

## Total Utility vs Marginal Utility

Total utility is the sum of satisfaction from consuming a given quantity of a good. Marginal utility is the additional satisfaction from consuming one more unit. The two move together but at different rates, and the gap between them drives most of consumer behavior.

The famous [law of diminishing marginal utility](/blog/diminishing-marginal-utility) says that as you consume more of something, each additional unit delivers less extra satisfaction. The first slice of pizza is bliss; the fifth is uncomfortable. Total utility may still rise with the fifth slice, but marginal utility is collapsing toward zero — and can even turn negative if you keep eating.

## The Utility Function

A utility function is a mathematical representation that maps consumption bundles to satisfaction levels, written as U(x, y, z, ...). It is the formal tool economists use to model preferences and make consumer theory tractable. The function itself is hypothetical, but its shape encodes everything about how someone trades off goods.

Common functional forms include Cobb-Douglas (U = x^a · y^b), constant elasticity of substitution, and quasi-linear utility. Each captures different patterns of substitution between goods. The function need not produce meaningful absolute numbers under ordinal utility — only the rankings of bundles matter, and any monotonic transformation gives the same predictions.

## The 1870s Marginalist Revolution

For most of economic history, value was thought to come from labor or production cost. Then in the 1870s, three economists working independently — Carl Menger in Vienna, William Stanley Jevons in Manchester, and Léon Walras in Lausanne — proposed that value comes from marginal utility. This was the marginalist revolution, and it reshaped economics permanently.

![From Bernoulli's paradox to prospect theory, utility evolved over three centuries of economic thought.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20800%20149%22%20width%3D%22800%22%20height%3D%22149%22%20role%3D%22img%22%3E%3Ctitle%3ETimeline%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Cline%20x1%3D%22137.5%22%20y1%3D%2255%22%20x2%3D%22662.5%22%20y2%3D%2255%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%223%22%2F%3E%3Ccircle%20cx%3D%22137.5%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22137.5%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E1%3C%2Ftext%3E%3Ctext%20x%3D%22137.5%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3E1738%3C%2Ftext%3E%3Ctext%20x%3D%22137.5%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EBernoulli%3A%20log%20utility%3C%2Ftext%3E%3Ccircle%20cx%3D%22312.5%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22%232563eb%22%20stroke%3D%22%232563eb%22%20stroke-width%3D%223%22%2F%3E%3Ctext%20x%3D%22312.5%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3E2%3C%2Ftext%3E%3Ctext%20x%3D%22312.5%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3E1870s%3C%2Ftext%3E%3Ctext%20x%3D%22312.5%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EMarginalist%20Revolution%3C%2Ftext%3E%3Ccircle%20cx%3D%22487.5%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22487.5%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E3%3C%2Ftext%3E%3Ctext%20x%3D%22487.5%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3E1944%3C%2Ftext%3E%3Ctext%20x%3D%22487.5%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EvNM%20expected%20utility%3C%2Ftext%3E%3Ccircle%20cx%3D%22662.5%22%20cy%3D%2255%22%20r%3D%2224%22%20fill%3D%22white%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22662.5%22%20y%3D%2260%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2215%22%20font-weight%3D%22700%22%20fill%3D%22%230f172a%22%3E4%3C%2Ftext%3E%3Ctext%20x%3D%22662.5%22%20y%3D%22101%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2212%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3E1979%3C%2Ftext%3E%3Ctext%20x%3D%22662.5%22%20y%3D%22119%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3EProspect%20theory%3C%2Ftext%3E%3C%2Fsvg%3E)

*From Bernoulli's paradox to prospect theory, utility evolved over three centuries of economic thought.*

Their key insight resolved the diamond-water paradox: water is essential but cheap because the marginal unit is abundant; diamonds are useless but expensive because the marginal unit is scarce. Price reflects marginal utility, not total utility. From this single observation, modern microeconomics emerged.

## Utility Maximization and the Equimarginal Principle

Consumers are assumed to choose the bundle of goods that maximizes total utility subject to their budget constraint. This is the central optimization problem of consumer theory, and its solution gives us demand curves. The math is calculus, but the intuition is dead simple — spend each dollar where it does the most good.

The equimarginal principle formalizes this. At the optimum, the marginal utility per dollar must be equal across all goods you buy: MU_x / P_x = MU_y / P_y = ... If coffee gives you twice the marginal utility of tea per dollar, you'll buy more coffee until that ratio equalizes.

### The Budget Constraint

Your budget constraint is a straight line representing every combination of goods you can afford. With $20 and coffee at $4 and donuts at $2, you could buy 5 coffees and 0 donuts, 0 coffees and 10 donuts, or any line between. The slope reflects the relative price.

### Consumer Equilibrium

The optimal bundle sits where the highest reachable indifference curve just touches the budget line. At that tangency, the slope of the indifference curve (the marginal rate of substitution) equals the price ratio. That's the equimarginal principle restated geometrically.

## Indifference Curves

An indifference curve plots all combinations of two goods that deliver the same utility. They slope downward — to maintain satisfaction with less of one good, you need more of the other. They are convex to the origin because of diminishing marginal utility — you give up less of the abundant good per extra unit of the scarce one.

Indifference curves never cross (that would imply contradictory rankings) and higher curves represent higher utility. Layered together they create a "preference map" that, combined with a budget line, predicts exactly what a rational consumer will buy.

### Worked Example: Coffee and Donuts

Suppose you have $20, coffee costs $4, and donuts cost $2. Your utility function is U = C · D. The optimum sets MU_C / P_C = MU_D / P_D, which simplifies to D/4 = C/2, or D = 2C. Plug into the budget: 4C + 2(2C) = 20, so C = 2.5 and D = 5. You'd buy 2 to 3 coffees and 5 donuts to maximize satisfaction.

## Types of Utility

Marketers and applied economists break utility into five practical categories that explain why the same physical good can be worth wildly different amounts in different settings. Each type reflects a transformation that adds value beyond the raw object itself.

![The five practical categories of utility show how value is added beyond the raw physical good.](data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%20760%20211%22%20width%3D%22760%22%20height%3D%22211%22%20role%3D%22img%22%3E%3Ctitle%3EHierarchy%3C%2Ftitle%3E%3Crect%20width%3D%22100%25%22%20height%3D%22100%25%22%20fill%3D%22%23f8fafc%22%2F%3E%3Crect%20x%3D%22300%22%20y%3D%2220%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22%232563eb%22%2F%3E%3Ctext%20x%3D%22380%22%20y%3D%2254%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2214%22%20font-weight%3D%22700%22%20fill%3D%22white%22%3EUtility%20Types%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20110%20105.5%20L%20110%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%2230%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22110%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EForm%3C%2Ftext%3E%3Ctext%20x%3D%22110%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3Einputs%20transformed%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20290%20105.5%20L%20290%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22210%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22290%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPlace%3C%2Ftext%3E%3Ctext%20x%3D%22290%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3Elocation%20value%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20470%20105.5%20L%20470%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22390%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22470%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3ETime%3C%2Ftext%3E%3Ctext%20x%3D%22470%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3Etiming%20value%3C%2Ftext%3E%3Cpath%20d%3D%22M%20380%2078%20L%20380%20105.5%20L%20650%20105.5%20L%20650%20133%22%20stroke%3D%22%23cbd5e1%22%20stroke-width%3D%222%22%20fill%3D%22none%22%2F%3E%3Crect%20x%3D%22570%22%20y%3D%22133%22%20width%3D%22160%22%20height%3D%2258%22%20rx%3D%228%22%20fill%3D%22white%22%20stroke%3D%22%230891b2%22%20stroke-width%3D%222%22%2F%3E%3Ctext%20x%3D%22650%22%20y%3D%22158%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2213%22%20font-weight%3D%22600%22%20fill%3D%22%230f172a%22%3EPossession%3C%2Ftext%3E%3Ctext%20x%3D%22650%22%20y%3D%22176%22%20text-anchor%3D%22middle%22%20font-family%3D%22system-ui%2C-apple-system%2Csans-serif%22%20font-size%3D%2210%22%20fill%3D%22%2364748b%22%3Eownership%20transfer%3C%2Ftext%3E%3C%2Fsvg%3E)

*The five practical categories of utility show how value is added beyond the raw physical good.*

- **Form utility:** transforming inputs into something more valuable. Flour into bread, lumber into [furniture](/blog/furniture-fixtures-and-equipment), code into software.
- **Place utility:** value created by location. Water in a desert, an ATM at the airport, a coffee shop in a train station.
- **Time utility:** value created by timing. Turkey at Thanksgiving, umbrellas on rainy days, ice cream in summer.
- **Possession utility:** value from legal ownership transfer. A car you can drive versus one in a dealer lot.
- **Information utility:** value from knowledge. A stock tip, a recipe, a map of where the fish are biting.

## Expected Utility Theory

When outcomes are uncertain, simple utility maximization isn't enough — you need expected utility theory. Developed formally by John von Neumann and Oskar Morgenstern in 1944, it says rational agents under uncertainty maximize the probability-weighted average of utility across possible outcomes, not the average of dollar payoffs.

![Three risk attitudes mapped by utility function shape and preference for certain vs. uncertain 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*Three risk attitudes mapped by utility function shape and preference for certain vs. uncertain payoffs.*

This distinction matters enormously. A 50/50 gamble between $0 and $200 has an expected value of $100. But for most people the expected utility is less than U($100), because the utility of $200 isn't twice the utility of $100. The utility function is concave — and that concavity is exactly what we mean by risk aversion.

### Risk Attitudes

Three shapes of utility function describe three attitudes toward risk:

- **Risk-averse:** concave utility. Diminishing marginal utility of wealth means each extra dollar matters less, so guaranteed money beats equivalent-EV gambles. This describes most adults most of the time.
- **Risk-neutral:** linear utility. The agent cares only about expected value. This is closer to large institutions diversified across many bets.
- **Risk-loving:** convex utility. The agent prefers gambles to certain payouts. Rare in adults but visible in lottery and casino behavior — usually for small stakes where entertainment value dominates.

### The St. Petersburg Paradox

In 1738, Daniel Bernoulli described a coin-flip game with infinite expected value: keep flipping until tails, win 2^n dollars where n is the number of heads. Despite infinite EV, nobody will pay more than a few dollars to play. Bernoulli's solution was to introduce logarithmic utility — the marginal utility of wealth diminishes, so infinite-EV games can have finite expected utility. This was expected utility theory's first appearance, more than 200 years before von Neumann-Morgenstern formalized it.

## Behavioral Departures from Classical Utility

Classical expected utility theory predicts choices reasonably well in many settings but breaks down in others. Behavioral economics — pioneered by Daniel Kahneman and Amos Tversky — documented systematic deviations and built better descriptive models. The math is now richer, and so is the understanding of why people make the financial choices they do.

Prospect theory, published by Kahneman and Tversky in 1979, replaced the utility function with a "value function" that is concave for gains, convex for losses, and steeper on the loss side. People evaluate outcomes relative to a reference point, not absolute wealth. This single change explains dozens of puzzles in finance and consumer behavior.

### Loss Aversion

Empirically, losses hurt about twice as much as equivalent gains feel good. Losing $100 stings roughly as much as winning $200 delights. This loss aversion explains why investors hold losing stocks too long, why people refuse small-stakes coin flips with positive EV, and why insurance companies stay in business.

### Hyperbolic Discounting

Classical theory assumes people discount future payoffs exponentially at a constant rate. In practice, people use hyperbolic discounting — they're impatient now but more patient later. This produces time-inconsistent preferences: you commit at the gym on Monday and skip it Wednesday. The same psychology explains why retirement saving is so hard.

## Utility in Finance

Modern finance is built on utility theory whether practitioners realize it or not. Markowitz's mean-variance portfolio theory implicitly assumes investors maximize a quadratic utility function, where only the mean and variance of returns matter. This framework gave us efficient frontiers, diversification, and the modern portfolio.

The Capital Asset Pricing Model goes further, assuming a representative agent with concave utility who prices assets according to their covariance with aggregate consumption. Insurance demand falls directly out of risk-averse utility — paying a small certain premium beats facing a small probability of catastrophic loss. Even consumer [surplus](/blog/surplus-definition-economics), the area between the demand curve and price, equals the total utility consumers gain minus what they pay.

## Practical Applications of Utility Theory

Utility shows up far beyond academic economics. Cost-benefit analysis translates dollar costs and benefits into utility-equivalent terms to evaluate public projects. Healthcare uses Quality-Adjusted Life Years (QALYs), which weight years of life by health-related utility, to compare treatment value.

Welfare economics aggregates individual utilities into social welfare functions to evaluate policy. Behavioral finance uses utility-based models to design better retirement plans, default options, and savings nudges. Even your subscription pricing decisions implicitly weigh marginal utility against monthly cost.

## Limits of Utility Theory

Utility theory has well-known boundaries. Interpersonal utility comparisons are impossible in any rigorous cardinal sense — we can't truly say one person's happiness exceeds another's. This makes social welfare conclusions philosophically fragile.

Utility theory also misses process utility (the joy of choosing or doing, separate from the outcome) and struggles with hedonic adaptation, where people quickly return to baseline happiness after good or bad shocks. Reference dependence, partly addressed by prospect theory, still complicates any simple utility story. Modern well-being economics and life-satisfaction surveys try to fill these gaps with direct measurement rather than inferred preferences.

## Authoritative Sources

For deeper background and primary-source data on this topic, the following authoritative sources are useful starting points:

- [Bureau of Economic Analysis](https://www.bea.gov/)
- [Bureau of Labor Statistics](https://www.bls.gov/)
- [Federal Reserve](https://www.federalreserve.gov/)
- [Federal Reserve Economic Data (FRED)](https://fred.stlouisfed.org/)

## Conclusion

The utilities definition economics gives us — satisfaction or benefit derived from consumption — looks simple but supports a vast intellectual edifice. From the 1870s marginalists to von Neumann-Morgenstern to Kahneman's prospect theory, utility has been the unifying concept connecting consumer choice, asset pricing, insurance, and behavioral finance.

Three takeaways worth keeping. First, marginal utility — not total utility — drives prices and decisions, which is why diamonds cost more than water. Second, concave utility explains risk aversion and therefore the entire architecture of insurance, diversification, and portfolio theory. Third, real humans depart from classical utility in predictable ways: loss aversion, reference dependence, and hyperbolic discounting shape your financial behavior whether you notice or not.

Use utility as a thinking tool. When you face a choice, ask which option delivers the most satisfaction per dollar, factor in your own risk tolerance, and watch for the behavioral traps that distort the math. As neuroeconomics and well-being research advance, expect utility theory to keep evolving — but the core intuition will stay the same.

Ready to put this knowledge to work? Try Warren, your AI financial advisor — get personalized, conflict-free guidance at heywarren.com

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## Related Reading

**More from Warren**:

- [What Is a Scalping Trade?](/blog/scalping-trade)
- [What Economic System Is America? The Short Answer](/blog/what-economic-system-is-america)
**Authoritative sources**:
- [SEC Investor.gov — Investing Basics](https://www.investor.gov/introduction-investing/investing-basics)
- [FINRA — Investor Education](https://www.finra.org/investors)