The short version
- A share is a small piece of ownership in a company, with a claim on its future profits.
- You buy shares through a regulated broker; the exchange matches buyers and sellers during set hours.
- Broad index funds, low costs, patience and diversification are the usual starting points for new investors.
This is our stock market for beginners guide, written for someone who has never bought a share. It covers what a share is, how prices are set, what exchanges and brokers do, how dividends and indices work, and the habits that help most over long periods. There are no tips here and no predictions, just the machinery.
What a share actually is
A company that wants to raise money can sell pieces of itself to investors. Each piece is a share, and owning one makes you a part-owner. If the company has 100 million shares and you own 100, you own one-millionth of it. As an owner you are entitled to a proportional slice of whatever profits the company decides to pay out, and ordinary shares usually carry a vote at the annual meeting.
The first sale of shares to the public is called an initial public offering, or IPO. After that, the company is rarely involved in trading. Investors buy and sell existing shares with one another on a stock exchange, and the price moves as their views of the company change.
How the stock market works day to day
An exchange such as the New York Stock Exchange or Nasdaq is a regulated marketplace that matches orders from buyers and sellers. Regular trading on both runs from 09:30 to 16:00 New York time on weekdays. Other major venues have their own sessions: London trades from 08:00 to 16:30, Frankfurt's Xetra from 09:00 to 17:30 and Tokyo from 09:00 to 11:30 and 12:30 to 15:30, local time.
At any moment there is a best price someone will pay (the bid) and a best price someone will accept (the ask). When you place a market order, you accept the best available price. A limit order sets the highest price you will pay or the lowest you will accept, and waits until the market reaches it. For large, busy companies the gap between bid and ask is usually tiny; for small companies it can be wide.
After a US trade, ownership formally changes hands one business day later. This settlement cycle is known as T+1.
Why share prices move
In the short run, prices move whenever buyers are keener than sellers or the reverse. News drives much of that: quarterly earnings, product launches, changes in management, interest-rate decisions, economic data. What matters is not whether news is good or bad in itself, but how it compares with what was already expected. A company can report record profits and see its shares fall because investors hoped for more.
Over long periods, share prices have tended to track the growth of company earnings and the dividends paid out of them. That link is what separates shares from assets with no cash flow behind them. It is a tendency, not a guarantee: some companies shrink or fail, and whole markets have spent years below a previous peak.
Brokers, accounts and custody
Individuals do not trade directly on an exchange. You use a broker, a firm licensed to place orders for clients. In most major markets, the broker holds your shares in a nominee account on your behalf, legally separate from the broker's own assets. If a regulated broker fails, those assets should be returned to clients, and many countries also run a compensation scheme up to a limit.
Some countries offer tax-advantaged wrappers for investing. In the UK, for example, the annual ISA allowance for 2026/27 is £20,000. Rules vary widely, so check what applies where you live. Our broker checklist covers regulation, costs and the questions worth asking before you sign up anywhere.
Dividends: the cash side of shares
Many established companies pay part of their profits to shareholders as a dividend, typically every quarter in the US. The dividend yield is the annual dividend divided by the share price. In an illustrative example, a company paying $2.40 a year whose shares cost $80 has a yield of 2.40 ÷ 80 = 3%. Buy 25 shares for $2,000 and you would receive $60 a year in dividends, before any tax, if the payout stayed the same.
Dividends are never guaranteed and can be cut. A very high yield sometimes signals that the market expects a cut, because the price has fallen. To receive a dividend you must own the share before its ex-dividend date; on that date the price usually drops by roughly the amount of the payment. Reinvesting dividends, rather than spending them, is one of the main ways returns compound over decades.
Valuation in one ratio
The most quoted valuation measure is the price-to-earnings (P/E) ratio: the share price divided by earnings per share over a year. Using round illustrative numbers again, a share at $80 with earnings of $4 per share has a P/E of 20, meaning investors pay $20 for each $1 of annual profit. A high P/E usually reflects expectations of faster growth; a low one can mean a bargain or a business in trouble. On its own the number tells you little, but it is a useful starting question.
Indices, index funds and ETFs
An index tracks a basket of shares to show how a market is doing. The S&P 500 follows around 500 large US companies weighted by their float-adjusted market value; the Dow Jones Industrial Average follows 30 companies weighted by share price; the Nasdaq Composite covers everything listed on Nasdaq; the FTSE 100, DAX and Nikkei 225 play similar roles in the UK, Germany and Japan.
You cannot buy an index directly, but you can buy a fund that copies one. An exchange-traded fund (ETF) is a fund whose units trade on an exchange like a share. A single purchase of a broad index ETF spreads your money across hundreds of companies, which is why index funds are the usual first holding for new investors. The main cost is the fund's annual charge, covered in our fees guide.
Risk, diversification and time
Individual companies can lose most of their value, so owning many of them, across sectors and countries, reduces the damage any single failure can do. That is diversification. It does not protect you from a broad market fall, and falls of 20% or more happen from time to time.
Time is the other defence. Money you might need within a few years is generally better kept out of shares, because you may be forced to sell after a fall. Money you can leave alone for a decade or more has historically had a better chance of riding out bad years, though past patterns are no promise.
The stock market for beginners: a calm first plan
- Decide what the money is for and when you might need it.
- Keep an emergency cash buffer separate from investments.
- Choose a regulated broker or platform and understand every fee it charges.
- Consider a broad, low-cost index fund before picking individual companies.
- Add money regularly, reinvest dividends and review once or twice a year rather than daily.
When stock market headlines get loud, our homepage has a short guide to reading market news without being rushed by it.
Reader questions
How much money do I need to start investing in shares?
Many brokers now allow small amounts and fractional shares, so the practical minimum can be low. What matters more is that the money is not needed soon and that fees are small relative to the amount invested.
What is the difference between a share and an ETF?
A share is ownership in one company. An ETF is a fund, traded on an exchange like a share, that usually holds many companies at once, often by copying an index such as the S&P 500.
Do I pay tax on dividends and gains?
In most countries, yes, although allowances and tax-advantaged accounts can reduce or remove the tax. The rules are national, so check your own tax authority's guidance or speak to a qualified adviser.
Sources
- US Securities and Exchange Commission, investor education on stocks and T+1 settlement
- Exchange trading-hours information from NYSE, Nasdaq, London Stock Exchange, Deutsche Börse and Japan Exchange Group
- HM Revenue & Customs, Individual Savings Accounts