A plain-English map of how buying and selling stock actually works — shares, orders, settlement, and dividends — written the way I wish someone had explained it to me.
Last updated July 24, 2026
Straight up: this is the one page in this series I actually trade. Small-cap momentum in that 9:35–11:00 AM window is stock trading — buying and selling shares of real companies, no options, no futures, no extra leverage beyond an ordinary margin account. I've also spent 25+ years on the slow end of this same instrument, position trading and investing, including two decades in an investment club. (The full story on how those two speeds coexist is in Types of Trading — Where I sit.) Everything below is the plain-English foundation the rest of this site builds on — see the glossary for every term defined in more depth.
A company that wants outside investors doesn't sell itself whole — it slices itself into millions of identical little pieces and sells those instead. Each piece is a share. Own one share of a company with a million shares outstanding and you own one-millionth of it: one-millionth of its profits, one-millionth of a vote at the shareholder meeting. Buy more shares, own a bigger slice. That's the entire concept a stock market is built on top of.
Shares change hands on an exchange — the NYSE or the Nasdaq for most US stocks — where a computerized order book matches buyers and sellers thousands of times a second. You never actually meet the person on the other side of your trade; your broker routes the order, the exchange (or a market maker) fills it, and the whole thing happens in a fraction of a second.
Every stock trade comes down to two choices stacked on top of each other: which direction, and how precisely you control the price.
Buy or sell immediately at the best price currently available. Fast and (almost) always fills — but you don't control the exact price you get.
Buy or sell only at your specified price or better. The price is protected — but the order might never fill if the stock never reaches it.
Buy shares expecting the price to rise. The default way almost everyone starts. Your loss is capped at what you paid; your gain isn't capped at all.
Borrow shares, sell them now, buy them back later hoping for a lower price. Needs a margin account — and the loss has no ceiling if the stock rises instead.
Underneath the chart, a stock's price is a running argument between buyers and sellers about what the company is worth — and a handful of things tend to restart that argument. A catalyst (earnings, guidance, an FDA approval, a new contract) gives the market a real reason to re-price a stock. Float — how many shares are actually available to trade — determines how far a given amount of buying or selling pressure can push the price; a tight float moves harder on the same dollar volume than a heavily-traded mega-cap. Broader sector and market sentiment pulls stocks in the same industry together, even absent company-specific news. And the two most common fundamental yardsticks, EPS and the P/E ratio, are how longer-term investors judge whether today's price is cheap or expensive relative to the business underneath it.
Clicking "buy" doesn't instantly make you the owner of record — there's a clearing step behind the scenes. US stock trades settle T+1: one business day after the trade date. Until then, your shares (or, on a sale, your cash) are technically still in transit. Your broker holds your shares in "street name" — registered in the broker's name on your behalf, which is why they show up in your account instantly even though full settlement takes a day. If your broker ever failed, SIPC insurance covers up to $500,000 per customer, with a $250,000 sub-limit on cash — protection against the brokerage failing, not against your investments losing value.
The instrument doesn't change; the timeframe and the direction do. This site has a full breakdown of the five styles by holding period in Types of Trading — here's the short version as it applies specifically to stocks.
What: Buying and selling within the same session, no overnight hold. This is my main game — small-cap catalysts in the first 90 minutes.
Why: No overnight gap risk, and capital recycles the same day.
Risk: It's a market-hours job, and the research on beginner day traders is brutal — see Types of Trading for the full numbers.
What: Holding a position for days to weeks to capture one larger move.
Why: Far less screen time than day trading; fits around a full-time job.
Risk: Overnight and weekend gap risk on every position you hold.
What: Buying quality companies or funds and holding for years, letting dividends and compounding do the work.
Why: This is the other end of my own experience — 25+ years, including two decades in an investment club. Historically the most reliable way to build wealth, and it needs almost no daily attention.
Risk: Returns come slowly, and you ride out every downturn along the way.
What: Betting on a decline instead of a rise, using borrowed shares.
Why: The only way to profit directly from a stock falling, without buying an option.
Risk: Open-ended by design — a stock can only fall to zero, but it can rise without limit. Requires a margin account and locating shares to borrow.
Commission-free trading is now the default at nearly every major US broker, and fractional shares mean you can start with a handful of dollars rather than the full share price. The bigger decision is cash account vs. margin account: a cash account can't lose more than you deposit and doesn't allow short selling; a margin account unlocks leverage, shorting, and faster reuse of proceeds — along with the risk that comes with borrowed money. Which brokers fit which style is the whole point of my broker comparison.
This is the broker my own 9:35–11:00 AM trades run through — commission-free, fractional shares, and real-time data without a separate paid feed. It's not the only option; see the full broker comparison for how it stacks up against TradeZero, Robinhood, and the rest.
Read the full Webull reviewThe honest risk note. A single stock can still go to zero, and concentrating everything in one name is the single most common way beginners get hurt — diversification exists specifically to blunt that. Margin and short selling add real, open-ended risk beyond that. Nothing here is financial advice; trade size you can actually afford to lose, and understand an order type before you use it live.
Mark Douglas's classic on trading psychology — the book most people mean when they say "the mental game matters more than the strategy." A good first read before you risk real money on any of the four styles above. See my full book reviews for the rest of what I've actually read.
"Stock" refers to ownership in a company in general; a "share" is one countable unit of it — the thing you actually buy and sell. People use the words interchangeably, but a share is the precise unit.
No — fractional shares let most brokers sell you a few dollars' worth of even an expensive stock, and commission-free trading is standard now. The old idea that you need thousands of dollars to "start investing" is mostly outdated.
A market order in a liquid stock typically fills in a fraction of a second. A limit order can fill instantly if the price is already available, or sit unfilled indefinitely if the stock never reaches it. Either way, full settlement of the trade still takes until T+1.
Not on a plain long position in a cash account — the most you can lose is what you paid, down to zero. That changes the moment margin or short selling enters the picture: both can produce losses larger than your original stake.
Curious how stocks stack up against options, futures, forex, and crypto? See the full markets comparison.
