A share is an ownership interest in a company. Buying ordinary shares is different from trading a CFD that references the share price: the contract, ownership rights, costs and protections differ. Establish what the account actually lets you buy before comparing prices.

How Prices and Orders Fit Together

Every completed trade has a buyer and a seller. Prices change as the prices and quantities people are willing to trade change; it is too simple to say that rising prices mean more buyers than sellers.

The bid is an available buying price and the ask an available selling price, each for a particular quantity. Their difference is the spread. The last-traded price is a historical transaction, not a promise that your next order can execute there. Orders can execute on exchanges or through other venues and arrangements used by the broker.

A market order seeks execution without specifying a price boundary. A buy limit sets a maximum purchase price; a sell limit sets a minimum sale price. Limit orders may remain unfilled. See the SEC's order-type explanation.

Understand What You Own

Market capitalisation is share price multiplied by shares outstanding. A low price per share does not necessarily mean a small or cheap company. An index tracks a defined basket under its own methodology; it is not the entire stock market and is not itself a security you buy.

Volume measures trading activity in the stated period and feed. Higher activity does not guarantee tight spreads, stable prices or an easy exit during a disruption. A familiar company can still be a poor investment at a particular price.

Start With the Account and Objective

Decide whether you are studying long-term investing or frequent trading. Their research, turnover and cost assumptions differ. Check the broker's registration with the relevant regulator, charges, custody arrangements, order handling and product permissions.

Learn the interface in paper trading. Keep simulated results separate from live results. An affordable deposit is not automatically enough for a proposed position: minimum order size, fees and a loss budget matter.

Fractional-share availability and execution arrangements differ by broker, as FINRA explains. There is no universal starting sum suitable for every reader.

Can Losses Exceed the Purchase Amount?

For a fully paid long share purchase without borrowing, the share's value can fall to zero. Borrowing, short selling and derivatives introduce different obligations and can create losses beyond the initial deposit. Do not apply the fully paid share example to every product available in a cash-labelled account.

US securities day-trading margin rules are also in transition under FINRA's 2026 notice. Confirm the framework your broker currently applies instead of assuming a single account threshold applies worldwide.

Keep a record of orders, fills, costs and the reason for each decision. Our education hub develops these concepts without requiring you to place a live trade.

Risk Disclaimer: Trading involves substantial risk of loss. Past performance is not indicative of future results. See our full risk disclaimer.