What does one candle record?
A candle records an opening price, closing price, high and low for one interval. The body connects the open and close; the wick shows the extremes. A different interval tells a different part of the history.
Volume records activity on that venue. A chart summarises past transactions; it cannot guarantee the next move. The values here are invented.
Why can the execution price differ?
The spread separates the best bid from the best ask. Slippage is the difference between an expected price and the execution price. A larger order may use several price levels, and available orders can change.
Fees add another cost. The order book example shows how a three-unit order reaches beyond the first price level.
What can an order type control?
A market order prioritises execution at available prices. A limit order sets a price boundary and can remain unfilled. A stop order triggers an action at a threshold; the resulting order depends on the type and platform rules.
A stop-market order can execute at a worse price than expected. A stop-limit order can remain unfilled. A planned loss is not a guaranteed maximum loss.
How can you practise reading a trade?
Use a paper example. Write down the order type, quantity, available prices and fees. Calculate what would happen if the first price level disappeared. Compare your expected outcome with the rules of that order.
Keep hypothetical exercises separate from real orders. A simulated outcome does not establish that a strategy will work. Learn custody and key safety alongside market mechanics.