What an exchange is
A stock exchange is a regulated marketplace where buyers and sellers trade shares of public companies. Think of it as a highly organized auction that runs continuously during market hours, matching people who want to buy with people who want to sell.
The exchange itself does not set the price. Prices come from supply and demand among all the participants. The exchange's job is to provide a fair, orderly, and transparent place for those trades to happen, with rules that everyone follows.
NYSE vs Nasdaq
In the United States, the two giants are the New York Stock Exchange (NYSE) and the Nasdaq. The NYSE is the older, traditional exchange, historically associated with large, established companies. The Nasdaq launched in 1971 as the first electronic exchange and became the home of many technology companies.
In practice the differences matter less than they used to, since both are electronic and host huge companies. You will see the exchange listed on each asset page. Where a stock is listed rarely affects an everyday investor's decision.
How a trade actually happens
When you press buy in a brokerage app, your order is routed to the market, where it is matched with a seller at an agreed price, usually in a fraction of a second. You never deal with the other person directly; the exchange and your broker handle all of it behind the scenes.
This is why you can buy a share of a giant company in seconds from your phone. An enormous amount of infrastructure exists to make that single tap feel instant and safe.
💡 Listing is not the same as the company:A company lists its shares on an exchange to raise money and let investors trade them, but the exchange does not own or run the business. Owning a share means owning a slice of the company, not a slice of the exchange.
Market hours
US exchanges have set trading hours, normally 9:30 in the morning to 4:00 in the afternoon Eastern time, Monday through Friday, excluding holidays. Outside those hours, limited trading happens in pre-market and after-hours sessions, which carry extra risks.
Prices you see when the market is closed are the last traded values, which is why a stock can appear frozen overnight and then jump at the open if news broke while it was closed.
Why it matters to you
You do not need to think about exchanges day to day, but understanding them removes a lot of mystery. It explains why prices update in real time during the day, why they pause overnight, and how your order actually gets filled.
From there, the natural next steps are understanding the ticker symbols used to identify each stock and how to read a stock quote.