The stock market is a marketplace where buyers and sellers trade shares of publicly listed companies. When a company “goes public” through an IPO (Initial Public Offering), it sells a portion of ownership to the public in the form of shares. Those shares are then bought and sold on exchanges like the New York Stock Exchange (NYSE) or NASDAQ.
In simple terms: you buy a small piece of a company, hoping it will become more valuable over time – or that it will pay you dividends along the way.
The Key Players
|
Player |
Role |
|---|---|
|
Companies |
Issue shares to raise capital for growth |
|
Investors (retail) |
Buy/sell shares through brokerages |
|
Institutional investors |
Mutual funds, pension funds, hedge funds that trade in large volumes |
|
Brokers/brokerage firms |
Intermediaries that execute trades on behalf of investors |
|
Market makers |
Firms that provide liquidity by always being willing to buy or sell |
|
Stock exchanges |
Organized marketplaces (NYSE, NASDAQ) where trades are executed |
|
Regulators (SEC) |
Oversee markets, enforce rules, protect investors |
Primary vs Secondary Market
|
Market |
What Happens |
Who’s Involved |
|---|---|---|
|
Primary market |
Company issues new shares (IPO) |
Company ↔ initial investors |
|
Secondary market |
Investors trade existing shares |
Investor ↔ investor |
When you buy Apple stock on your brokerage app, you’re buying from another investor in the secondary market – Apple doesn’t receive that money. Apple only raised money in its primary market offering back in 1980.
How a Stock Trade Actually Happens
Step 1: You open a brokerage account (Fidelity, Schwab, Robinhood, etc.)
Step 2: You place an order – market order (buy at current price) or limit order (only buy at $X or lower)
Step 3: Your broker routes the order to an exchange or dark pool
Step 4: The order is matched with a seller at an agreed price
Step 5: Trade settles in T+1 (one business day after the trade date)
The entire process for a market order typically takes milliseconds.
How Stock Prices Are Determined
Stock prices change constantly based on supply and demand – shaped by:
|
Factor |
How It Moves Prices |
|---|---|
|
Company earnings |
Beat expectations = up; miss = down |
|
Economic data |
GDP, unemployment, inflation reports |
|
Interest rates |
Higher rates = lower stock valuations (generally) |
|
News and sentiment |
Positive news drives buying; negative drives selling |
|
Institutional flows |
Large fund buying/selling moves prices |
|
Market psychology |
Fear and greed – often irrational short-term |
Major US Stock Indexes
Indexes track the performance of groups of stocks – they’re not investments themselves, but benchmarks.
|
Index |
What It Tracks |
Components |
|---|---|---|
|
S&P 500 |
500 largest US companies |
500 stocks |
|
Dow Jones Industrial Average |
30 large US companies |
30 stocks |
|
NASDAQ Composite |
All NASDAQ-listed stocks |
~3,000 stocks |
|
Russell 2000 |
Small-cap US companies |
2,000 stocks |
When people say “the market went up today,” they’re usually referring to the S&P 500.
Bull Markets vs Bear Markets
|
Term |
Definition |
Typical Duration |
|---|---|---|
|
Bull market |
Rising prices (up 20%+ from recent low) |
Average 3-4 years |
|
Bear market |
Falling prices (down 20%+ from recent high) |
Average 9-14 months |
|
Correction |
Decline of 10-20% |
Weeks to months |
|
Crash |
Days to weeks |
Historically, bull markets last longer and rise more than bear markets decline – which is why long-term investors who stay invested generally come out ahead.
The Bottom Line
The stock market is a mechanism for businesses to raise capital and for investors to build wealth by participating in the growth of those businesses. It’s not a casino – over the long run, markets reflect the real growth of real companies. Short-term, prices are driven by emotion and noise. Long-term, they follow earnings and value. Understanding that difference is the foundation of every successful investing strategy.
