Basics
Basic4 Min Read
How the Stock Market Works
The road your order travels from the moment you tap Buy to the shares landing in your account.
An exchange is not a building; it is a matching engine. Its job is exactly one thing: bringing a buyer and a seller together on a price. Everything else is infrastructure built around that simple task.
The Order Book
Every stock has an order book: one side wants to buy, the other wants to sell.
| Side | What it says | Example |
|---|---|---|
| Bid | The highest price a buyer will pay | 500 shares at $100.20 |
| Ask | The lowest price a seller will take | 300 shares at $100.24 |
The gap between them is the spread. The moment a buy order touches the ask side, a trade happens and that number becomes the "last price." The price you see on screen is exactly that: the last executed trade — the past.
The Queue Rules
Matching follows two rules, both simple:
- Price priority — the better price trades first.
- Time priority — between two orders at the same price, the earlier one trades first.
That is why a "market" order eats through the book starting from the best opposing price and moving up. A large order doesn't fill at one price; it fills across several levels.
The Institutions in Between
You don't connect to the exchange directly. The chain looks like this:
The Journey of an Order
- YouTap "buy" in your broker's app.
- Your brokerChecks the order and your balance, then routes it to a market.
- Market maker or exchangeThe order matches against the other side of the book. This step usually takes a fraction of a second.
- SettlementThe trade is recorded and shares and cash change hands. In the US this is T+1: the next business day.
Session Hours
The US market runs in three parts. Istanbul times shift twice a year with US daylight saving; the Istanbul column below is the summer schedule.
| Session | New York | Istanbul (summer) | Character |
|---|---|---|---|
| Pre-market | 4:00 – 9:30 | 11:00 – 16:30 | Thin, jumpy, wide spreads |
| Regular session | 9:30 – 16:00 | 16:30 – 23:00 | Nearly all the volume |
| After-hours | 16:00 – 20:00 | 23:00 – 03:00 | Earnings reactions live here |
The two busiest minutes of the day are the open and the close. In the closing auction, index funds settle the day's inflows and outflows — which is why huge volume prints in the final minute.
Where You'll See It on This Site
The countdown on the home page shows the time to the next open or close. The Today's Flow strip lines up economic releases and earnings on one time axis; every time is written in both New York and Istanbul time.