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Lesson 1 of 8
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Lesson 1 · 7 min

What Is the Stock Market and How Does It Work?

Learn what stocks are, how exchanges work, and the key forces that move prices every day.

In this lesson you'll learn
What a stock actually is (and why companies issue them)
How stock exchanges like NYSE and NASDAQ work
What forces move stock prices up and down
The difference between bull and bear markets

What is a stock?

A stock (also called a share or equity) represents a small ownership stake in a company. When Apple has 15 billion shares outstanding and you own 10, you own 10/15,000,000,000th of Apple — tiny, but real.

Companies issue stock to raise money. Instead of borrowing from a bank, a company can sell ownership stakes to thousands of investors. Those investors hope the company grows and their stake becomes worth more over time.

Why companies issue stock
Private Company
Needs capital to grow
Issues Shares (IPO)
Sells ownership to investors
Public Company
Listed on NYSE / NASDAQ

How do stock exchanges work?

A stock exchange is the marketplace where buyers and sellers meet to trade shares. The two largest in the world are the New York Stock Exchange (NYSE) and NASDAQ. Every transaction — billions of them daily — is recorded and matched electronically in milliseconds.

How a stock trade happens in seconds
1
You place a buy order
via your broker app
2
Broker routes order
to the exchange
3
Exchange matches you
with a seller
4
Trade settles (T+1)
shares transferred

NYSE and NASDAQ differ slightly: NYSE is older and uses a hybrid of human traders and electronic matching. NASDAQ is fully electronic and is home to most major tech companies (Apple, Microsoft, Google, Amazon, Meta are all NASDAQ-listed).

What makes stock prices move?

At the most fundamental level, prices are set by supply and demand. If more people want to buy a stock than sell it, the price rises. If more want to sell, it falls. But what drives those decisions?

Earnings results

A company beating or missing earnings expectations is the single biggest short-term price mover.

Revenue growth

Investors pay premiums for companies growing revenue faster than expected.

Interest rates

Higher rates make bonds more attractive, pulling money away from stocks.

Economic data

GDP growth, unemployment, and inflation all signal how strong corporate profits might be.

News & sentiment

Product launches, lawsuits, CEO changes, and geopolitical events all cause price reactions.

Analyst upgrades

When a major bank raises a price target, institutional investors often buy — pushing the price up.

Bull markets vs bear markets

🐂
Bull Market

Prices rising 20%+ from recent lows. Usually driven by strong economic growth, rising corporate earnings, and investor optimism. The average bull market lasts about 5.5 years.

🐻
Bear Market

Prices falling 20%+ from recent highs. Driven by economic slowdowns, rising rates, or crises. The average bear market lasts about 10 months — much shorter than bull markets.

The key insight most beginners miss: bear markets are temporary, bull markets are the default state. Since 1950, the S&P 500 has spent roughly 78% of its time in bull market conditions. Long-term investors who hold through bear markets have always been rewarded.

Quick Knowledge Check
3 questions · test what you've just learned
1

What does owning a stock actually give you?

2

Which of the two major US exchanges is fully electronic with no human floor traders?

3

Historically, how long does the average bear market last compared to the average bull market?

✓ Key takeaways from Lesson 1
A stock is a fractional ownership stake in a publicly traded company.
Stocks trade on exchanges like NYSE and NASDAQ — prices are set by supply and demand.
Earnings, interest rates, economic data, and sentiment all move stock prices.
Bull markets (prices rising) last ~5× longer than bear markets — time in the market beats timing the market.
See real stock data on BriMindInvest

Now that you know what stocks are, explore real-time signals, price data, and AI scores for thousands of stocks — free, no account needed.

Explore Stocks →
Next: Lesson 2How to Read a Stock Quote