Definition. The difference between the best offer (ask) and the best bid.
How it works
The spread is the cost of immediacy: whoever wants to buy or sell right now pays it to the side waiting with a limit order. In liquid markets it's usually one tick.
Example
Bid 51,907, ask 51,908: the spread is 1 point. Just before a data release it can widen to several points.
What to watch out for
A wide spread signals low liquidity and the risk of slippage.
You'll find the full explanation with graphics, examples and exercises in the 🖥️ Order flow atlas space, and its use in the live market in the 🔴 Live Room. Both are available to Club members (in Polish).
