How Markets & Exchanges Work
Before you can trade, you need to understand where trading actually happens — and how exchanges match buyers with sellers every millisecond of every day. This infrastructure is invisible to most traders, but understanding it changes how you think about price.
What Is a Market?
A market is simply a place where buyers and sellers meet to exchange something at an agreed price. A fish market, a stock market, a crypto exchange — same concept. One person wants to sell, another wants to buy, and they find a price they both accept.
The key insight: price is never a fixed fact — it's the result of the most recent agreement between a willing buyer and a willing seller. When more people want to buy than sell, the price rises until enough sellers show up. When more want to sell, it falls until buyers step in.
Spot vs. Futures Markets
Spot Market
- You buy the actual asset
- No expiry date
- Can't lose more than you invest
- Lower fees, simpler
- Best for beginners
Futures / Derivatives
- You trade a contract (not the asset)
- Can use leverage (amplified risk)
- Can bet on falling prices (shorts)
- Liquidation risk — can lose everything
- For experienced traders only
The Order Book
The order book is the live list of all open buy and sell orders on an exchange. It shows you exactly who wants to buy at what price and who wants to sell at what price — in real time.
The current "price" = best ask (€62,250) if you're buying, best bid (€62,200) if you're selling. The €50 gap between them is the spread — the exchange's cut.
Market Orders vs. Limit Orders
Market Order
You say: "Buy now, whatever the price is." You get filled immediately at the best available ask price. Fast, but you accept whatever price the market gives you. In thin markets, this can be expensive (slippage).
Limit Order
You say: "Buy at €62,000, not a cent more." Your order sits in the order book and waits. If price comes down to €62,000 and sellers agree, you get filled. If not, it stays open. More control, but no guarantee of execution.
CEX vs. DEX
Centralized Exchange (CEX) — Binance, Coinbase, Kraken. A company runs the order book, holds your funds, and matches trades. Fast, liquid, easy to use. But: you don't control your keys. "Not your keys, not your coins."
Decentralized Exchange (DEX) — Uniswap, dYdX. Smart contracts on a blockchain run the exchange. You keep control of your wallet. But: usually slower, higher fees on-chain, and more complex.
For active trading: CEX. For holding long-term or DeFi strategies: DEX or hardware wallet.
Key Takeaways
- Price = the most recent agreement between a buyer and seller. It rises when buyers outnumber sellers.
- Spot = own the asset. Futures = trade a contract with leverage and liquidation risk.
- The order book shows all open buy/sell orders — the spread between best ask and best bid is the transaction cost.
- Market orders = instant, any price. Limit orders = your price, but may not fill.
- CEX = fast and liquid but you don't control keys. DEX = self-custody but more complex.
- Beginners: start spot, use limit orders, stick to top-tier CEXs