Think of a stock market as a massive, organized marketplace. But instead of selling fruits and vegetables, this market deals in tiny pieces of companies, called stocks or shares. When you buy a stock, you're buying a small slice of ownership in a public company.

Why does this market exist? For two main reasons. First, companies sell these small pieces of themselves to raise money. They use this cash to fund new projects, hire more people, or expand their business. Second, investors buy these pieces hoping the company will do well, making their slice of ownership more valuable over time.

While we talk about "the stock market" as a single concept, trading actually happens in specific places called stock exchanges. These are the formal venues where buyers and sellers come together. In the past, this happened on crowded physical trading floors. Today, most of it is done electronically.

In the United States, two exchanges dominate the landscape:

• The New York Stock Exchange (NYSE): One of the oldest and most famous exchanges in the world, the NYSE has a physical trading floor on Wall Street, though much of its trading is now electronic.
• The Nasdaq Stock Market: Unlike the NYSE, the Nasdaq has always been a fully electronic exchange. It's known for being home to many of the world's biggest technology companies.

When a company offers shares, they usually come in two main flavors: common and preferred. While both represent ownership, they have key differences that matter to investors.

Common Stock is what most people mean when they talk about buying stocks. It gives shareholders voting rights, meaning they can have a say in big company decisions, like electing the board of directors. The value of common stock can grow significantly if the company performs well, but it also carries more risk. If the company goes bankrupt, common stockholders are the last to get paid, if there's anything left.

Preferred Stock is a bit different. It typically doesn't come with voting rights. However, preferred stockholders have a higher claim on the company's assets and earnings. They are usually guaranteed a fixed dividend payment, which must be paid out before any dividends are paid to common stockholders. In a bankruptcy, they also get paid before common stockholders.

You can't just walk up to the New York Stock Exchange and buy shares of your favorite company. You need a middleman. This is where brokers and trading platforms come in.

A stockbroker is a licensed professional or firm that buys and sells stocks on your behalf. In the past, you'd have to call your broker on the phone to place an order. Today, most investors use online brokerage firms or trading platforms. These platforms are essentially websites or apps that allow you to manage your own investments, buying and selling stocks with just a few clicks.

When you decide to buy a stock, you place an order through your brokerage platform. Your broker then sends that order to an exchange. The exchange's system matches your buy order with someone else's sell order for the same stock at an agreed-upon price. This transaction happens in a fraction of a second. The price is determined by supply and demand: if more people want to buy a stock than sell it, the price goes up. If more want to sell than buy, it goes down.

Now, let's test your understanding of these core concepts.

Understanding these building blocks—what the market is, where it happens, what's traded, and how—is the first step to becoming a more informed investor.