Order types

The core order types

Makers and takers — the key idea

Limit orders make liquidity — they add resting size to the book and wait. Market orders take liquidity — they consume that resting size to trade now. Every transaction pairs a maker with a taker, and the taker is the one who chose to be aggressive, crossing the spread to get filled immediately.

This matters because aggression reveals urgency. A buyer who lifts the offer (a market buy) wanted in now, badly enough to pay up. A buyer who rests a bid is patient. When you watch aggressive buyers repeatedly lifting offers into a level, you are seeing conviction; when buying is all passive, resting and waiting, you are seeing hope. Order flow reading is, at its core, measuring which side is doing the aggressing.

Stops — the hidden accelerant

Stop orders deserve special respect. Because a stop becomes a market order when triggered, clusters of stops create pockets of forced, aggressive flow. A break of an obvious level can trigger a cascade of stops, each a market order pushing price further — a "stop run." This is why price sometimes lurches violently just past a well-watched level and then reverses: the aggressive flow was stops firing, not fresh conviction. Reading order types helps you tell a real break from a stop run.

Common mistakes

• Ignoring who is the aggressor. The same volume means opposite things depending on whether buyers or sellers were taking.
• Mistaking a stop run for conviction. A violent poke past a level can be stops firing, not real demand.
• Only using market orders. Paying the spread on every entry adds up; patient limit fills matter for cost.

Stops are liquidity, not protection

A stop order feels like protection to the person who placed it. Structurally, it is something else entirely: a market order waiting to happen, sitting at a known price, in a cluster with everyone else's.

This matters because stops congregate in predictable places — just beyond obvious highs and lows, round numbers, and well-watched levels. When price reaches such a zone, those stops trigger and become aggressive market orders all at once, producing a burst of one-directional flow that has nothing to do with anyone's conviction.

Two consequences follow. First, a violent poke through an obvious level followed by an immediate reversal is often a stop run rather than a genuine break — the flow was forced liquidation, not initiative, and once the stops are exhausted there is no one left to continue. Second, that pool of stops is genuinely useful liquidity for anyone who wants to fill size in the opposite direction, which is why price so often reaches just far enough to trigger them and no further.

None of this requires believing anyone is hunting you personally. It is simply what happens when many participants place the same conditional order in the same obvious place.

Where your order sits in the queue

One practical mechanic that shapes everything about passive execution: resting orders at a price are filled in the order they arrived. Being early in the queue at a level means you get filled; being late means price may trade at your level without ever reaching you.

This is why traders who work limit orders place them before price arrives rather than as it gets there. It is also why partial fills happen: price touches your level, trades some size, and moves away before your position in the queue comes up.

Order types you will actually use

Beyond the basic three, a few variants solve specific problems and are worth knowing by function rather than by name.

Stop-limit triggers at one price and then works as a limit rather than a market order. It protects you from catastrophic slippage in a fast move — and at the cost of possibly not being filled at all, which in a genuine emergency is the worse outcome. Useful for entries, dangerous for protective exits.

Market-if-touched is the mirror of a stop: it triggers a market order when price reaches a level in the favourable direction. Useful for taking profit at a target without watching.

Bracket orders attach a stop and a target to an entry automatically. Their real value is psychological rather than mechanical: the risk is defined at the moment of entry, when you are thinking clearly, rather than later when you are not.

The general principle: choose the order type from the job it does, and be especially deliberate with protective exits. A stop that might not fill is not a stop.

Slippage, and where it actually comes from

Slippage is usually described as bad luck. It is more often a predictable consequence of three things you control or can anticipate.

Order size relative to displayed depth. If you need 20 contracts and 6 are showing, you will trade through several levels by definition. Sizing to the book rather than to your conviction removes most avoidable slippage.

Timing. Market orders into a fast move, into thin hours, or in the seconds around a data release will fill worse — sometimes dramatically. The market is not thin because you arrived; you arrived when it was thin.

Stop placement in obvious clusters. A stop just beyond a widely watched level sits in a queue with everyone else's. When it triggers, it triggers alongside them, into whatever liquidity remains after the first ones have consumed it.

The practical adjustments are simple: size to the book, avoid market orders in the worst moments, and place stops slightly beyond the obvious cluster rather than inside it. None of these are clever — they are just the difference between costs that compound against you and costs that do not.

Where to actually place a stop

Since stops sit in clusters at obvious prices, the natural question is what to do about it — and there is a straightforward answer that costs very little.

Place the stop slightly beyond the obvious cluster rather than inside it. If everyone's protective order sits just below the round number, placing yours a few ticks further out means the sweep that triggers theirs does not necessarily trigger yours. The cost is a marginally wider stop and therefore a marginally smaller position; the benefit is not being taken out by the exact move your level was designed to survive.

The principle generalises: your stop should sit where the idea is invalidated, not where the chart looks tidy. If a fade at a wall is wrong once price accepts beyond the wall, then a few ticks of penetration is not invalidation — acceptance is. Placing the stop at the tidy price rather than the meaningful one is how correct trades get stopped for the wrong reason.

The discipline that makes this safe is sizing. A wider, more meaningful stop with correspondingly fewer contracts risks the same amount and survives more noise. It is strictly better, and it costs only the willingness to trade smaller.

Orders and the emotional dimension

A note that belongs here more than anywhere else in the course, because order mechanics are where discipline becomes concrete.

The moment of entry is the last moment you are fully rational about a trade. Before you are in, the analysis is clean; afterwards, every subsequent decision is contaminated by the position. This is why bracket orders matter more than their mechanical convenience suggests: attaching the stop and target at entry commits the decision while you can still make it well.

The same logic explains why moving a stop is so damaging. It is not that the new level is necessarily wrong; it is that the decision was made by someone in a worse state than the person who set the original. Traders who never move stops are not more disciplined by temperament — they have simply removed a decision that they know they cannot be trusted to make.

• Market = aggressive (takes liquidity); limit = passive (makes liquidity); stop = triggered market order.
• Every trade pairs a maker and a taker; the aggressor reveals urgency.
• Aggression winning = level failing; absorption winning = level holding.
• Stop clusters create forced flow and stop runs — don't mistake them for conviction.