The matching engine is the exchange or broker software that crosses buy and sell orders according to fixed rules.
In plain terms — You place a buy at €50; someone has a sell at €50. The matching engine brings them together and records the trade.
| Concept | Meaning |
|---|---|
| Order book | Queue of pending orders — see order-book |
| Match | Execution between compatible buy and sell |
| Price priority | Best price fills first (typical rule) |
| Time priority | Same price — first in, first out |
Order types (overview)
| Order | Behaviour |
|---|---|
| Market | Fill immediately at best available price |
| Limit | Fill only at stated price or better |
| Stop | Activates when price hits a threshold |
The matching engine applies market rules; the platform turns your buy-and-sell click into messages to the engine.
Matching engine vs market maker
Not the same: a market-maker supplies liquidity by quoting bid/ask; the matching engine pairs orders between participants (including orders against the market maker).