Equity Markets: What They Are & How They Work

What Is the Equity Market?

The equity market, also known as the stock market, is the collection of markets and exchanges where shares of publicly traded companies are issued, bought, and sold. When you purchase a share of stock, you are buying a fractional ownership stake in a company through the equity market. The equity market is the primary mechanism through which companies raise capital from the public and investors participate in corporate growth and profitability.

The equity market is divided into two fundamental segments: the primary market, where new shares are created and sold to investors for the first time, and the secondary market, where existing shares trade between investors on organized exchanges. Understanding how these two segments work together, who the major participants are, and how prices are determined gives you a foundational understanding of how modern financial markets operate.

The Primary Market: IPOs and New Issuances

The primary market is where companies sell new shares to investors for the first time to raise capital. The most well-known primary market transaction is the Initial Public Offering (IPO), in which a private company becomes publicly traded by offering shares to the public.

In an IPO, the company works with investment banks (called underwriters) to determine the offering price, the number of shares to sell, and the timing of the listing. The underwriters buy the shares from the company at a slight discount and sell them to institutional and retail investors at the offering price. The company receives the capital raised (minus underwriting fees), which it can use for expansion, debt repayment, research, or other corporate purposes.

The IPO process typically follows these steps:

Follow-on offerings (also called secondary offerings) occur when a company that is already public issues additional new shares. This dilutes existing shareholders but raises additional capital for the company. Secondary offerings can also include existing shareholders (like company founders or early investors) selling their shares to the public.

Direct listings are an alternative to traditional IPOs. In a direct listing, the company does not issue new shares or hire underwriters. Instead, existing shareholders sell their shares directly on the exchange on the first day of trading. Companies like Spotify and Coinbase went public via direct listings.

The Secondary Market: Where Stocks Trade Daily

The secondary market is where investors buy and sell shares that have already been issued. When you place an order to buy Apple (AAPL) stock through your brokerage account, you are participating in the secondary market. The company (Apple) does not receive any money from your purchase — you are buying shares from another investor who is selling them.

The secondary market is vastly larger than the primary market in terms of daily trading volume. While a company may have one IPO, its shares trade millions of times daily on the secondary market for decades afterward.

Secondary market trading occurs on two types of venues:

Organized exchanges are formal, regulated marketplaces with specific listing requirements. The two major U.S. exchanges are:

Over-the-counter (OTC) markets handle trading in securities not listed on major exchanges. The OTC market includes smaller companies, foreign companies trading via ADRs, and some penny stocks. OTC-traded securities typically have less liquidity, lower transparency, and higher risk than exchange-listed stocks.

Market Participants

The equity market functions through the interaction of several types of participants, each playing a distinct role.

Retail investors are individual investors who buy and sell securities through personal brokerage accounts. Retail trading has surged with the advent of commission-free platforms like Schwab, Fidelity, and Robinhood. While individual retail trades are small, collectively retail investors represent approximately 20% to 25% of U.S. equity trading volume.

Institutional investors are large organizations that invest on behalf of others. They are the dominant force in equity markets, accounting for roughly 70% to 80% of daily trading volume.

Market makers are specialized firms that provide liquidity by continuously posting bid and ask prices for securities. They profit from the bid-ask spread — the difference between the price at which they are willing to buy and the price at which they are willing to sell. Market makers are essential to a functioning equity market because they ensure that there is always a buyer for sellers and a seller for buyers, even in volatile conditions.

Market makers like Citadel Securities, Virtu Financial, and GTS handle a significant portion of all U.S. equity trades. They use sophisticated algorithms and technology to manage inventory risk and maintain tight spreads.

Price Discovery: How Stock Prices Are Determined

Price discovery is the process by which the equity market determines the price of a stock at any given moment. It is the result of all buyers and sellers expressing their views on a stock's value through the orders they place.

The mechanism works through the continuous matching of buy and sell orders:

• Buy orders (market orders and limit orders) represent demand — investors willing to pay a certain price or higher
• Sell orders represent supply — investors willing to accept a certain price or lower
• The current price is the most recent price at which a buy order and sell order were matched

When more buyers than sellers exist at the current price, the price rises until enough sellers emerge to meet the demand. When more sellers than buyers exist, the price falls until enough buyers step in. This continuous balancing act produces the real-time price quotes you see on your screen.

Factors that influence price discovery:

Price discovery works best in liquid markets with many participants, transparent information, and low transaction costs. When these conditions are met, stock prices tend to reflect available information quickly and efficiently — a concept known as the Efficient Market Hypothesis.

Global Equity Markets

Equity markets operate worldwide, each with distinct characteristics, regulatory environments, and trading hours.

Developed markets (U.S., Europe, Japan, Australia) tend to have stronger regulatory frameworks, higher liquidity, better corporate governance, and more stable currencies. They offer lower risk but potentially lower growth.

Emerging markets (China, India, Brazil, South Korea, Taiwan) offer exposure to faster-growing economies but with higher political risk, currency volatility, and regulatory uncertainty. Emerging market classification by index providers like MSCI has significant implications for capital flows.

The interconnection of global equity markets means events in one market can rapidly affect others. When Asian markets sell off overnight, European and U.S. markets often open lower, and vice versa. This globalization of equity markets has increased correlation and reduced diversification benefits compared to decades past.

The Economic Function of Equity Markets

Equity markets serve several critical functions in a modern economy.

Capital formation. Companies raise capital through the equity market to fund growth, innovation, and job creation. Without equity markets, companies would rely solely on bank loans and retained earnings, limiting their ability to scale. Amazon, Tesla, and thousands of other companies used IPO proceeds and subsequent equity offerings to fund their growth into major employers and innovators.

Wealth creation. Equity markets allow broad participation in economic growth. When you own index funds or individual stocks, you benefit from corporate profit growth and economic expansion. Over the long term, the U.S. equity market has returned approximately 10% annually (before inflation), making stock ownership one of the most effective wealth-building tools available.

Liquidity. Equity markets provide the ability to convert ownership stakes into cash quickly and at transparent prices. This liquidity encourages investment because investors know they can exit their positions when needed, unlike private investments that may take months or years to sell.

Information aggregation. Stock prices aggregate the views of millions of participants, incorporating information about company performance, industry trends, and macroeconomic conditions. This information function helps allocate capital to its most productive uses.

How Individual Investors Access Equity Markets

Getting started in the equity market is straightforward for most investors.

Open a brokerage account with a reputable broker. Major options include Charles Schwab, Fidelity, Vanguard, and Interactive Brokers for serious investors, or Robinhood and Webull for beginners seeking simplicity. Most brokers offer commission-free trading on U.S. stocks and ETFs.

Choose your investment approach. You can buy individual stocks, index funds that track broad market benchmarks, sector-specific ETFs, or international funds. For most new investors, starting with a broad index fund like the S&P 500 (SPY or VOO) provides instant diversification across 500 large U.S. companies.

Understand order types. A market order buys at the current price immediately. A limit order lets you set the maximum price you are willing to pay. A stop-loss order protects against large losses by automatically selling if the stock drops to a specified price.

Frequently Asked Questions

What is the difference between the equity market and the stock market?

The terms are essentially interchangeable. "Equity market" and "stock market" both refer to the system of markets and exchanges where shares of publicly traded companies are bought and sold. "Equity market" is the more formal, technical term used in finance and academia, while "stock market" is the common, everyday term. Some practitioners use "equity market" to include all equity-related instruments (stocks, ETFs, equity options, equity futures), while "stock market" may refer more narrowly to common stocks.

How do equity markets affect the economy?

Equity markets impact the economy through the wealth effect (rising stock prices make consumers feel wealthier and spend more), capital allocation (companies with high stock prices can raise capital more easily for investment and hiring), and business confidence (a strong equity market encourages corporate expansion). A declining equity market has the reverse effects — reduced consumer spending, tighter capital access, and lower business confidence, which can contribute to economic slowdowns or recessions.

Can you invest in foreign equity markets?

Yes. You can access foreign equity markets through several channels: ADRs (American Depositary Receipts) that trade on U.S. exchanges, international ETFs like the Vanguard FTSE Developed Markets ETF (VEA) or Vanguard FTSE Emerging Markets ETF (VWO), or direct access through brokers like Interactive Brokers that support trading on foreign exchanges. International diversification reduces portfolio concentration in any single country's economy and can capture faster growth in developing markets.

What are equity market hours?

U.S. equity market regular trading hours are 9:30 AM to 4:00 PM Eastern Time, Monday through Friday (excluding market holidays). Pre-market trading typically runs from 4:00 AM to 9:30 AM ET, and after-hours trading runs from 4:00 PM to 8:00 PM ET. Global markets operate on their own schedules: the London Stock Exchange trades from 8:00 AM to 4:30 PM GMT, and the Tokyo Stock Exchange trades from 9:00 AM to 3:30 PM JST.

What drives equity market returns over the long term?

Over long periods, equity market returns are driven primarily by corporate earnings growth and dividend payments. The S&P 500's long-term average annual return of approximately 10% consists of roughly 5% to 7% from earnings growth and capital appreciation plus 2% to 3% from dividends. In the short term, sentiment, interest rates, and macroeconomic events cause significant volatility, but over decades, returns converge toward fundamental earnings growth plus dividends.