Trading · 61 / 86 · 2 min
Orders and the book
An order book is a list of people waiting to buy and sell. A market order takes what is there. A limit order waits for your price, and it may never fill.
The last price on a chart is a trade that already happened. Yours is the next one.
A worked case
Someone uses a market order because they want the price on the chart. The book is thin. They get a much worse fill. A limit would have waited, and might not have filled. They needed to choose which disappointment they were willing to have.
Market and limit
A market order says fill me now. In a thin book, now can be a much worse price. A limit order says only at this price or better. It can sit there while the market leaves.
The gap
The last price on a chart is a trade that already happened. Your trade is the next one, against the offers that are actually resting.
Look at the size available near the price, not only at the last dot.
The last price already happened
An order book is a list of resting bids and offers. A market order takes what is there, now, which in a thin book can be far from the last traded price. A limit order waits for your price and may never fill, while the market leaves and you sit in a coin you did not want to keep holding. Both are honest tools. They disappoint you in different directions. People who use a market order because they want the price on the chart have confused a history with an offer.
Thin books are where memecoins and small exchanges hurt. The volume course is the companion: a loud daily total can hide an empty book near the price. Look at the size available, not at the last dot.
Choose whether you need a fill now or a price. If you need both, you are hoping, and hope is not an order type.
Read it yourself
These links are the record. They are not a recommendation, and they are not instructions. A news story or a court paper can still be wrong about a detail. The check does not change because a famous name is in the story.
Apply the check
Open a question. The line is about this topic. It is not a verdict that anything is safe.
Whoever was resting on the book, and the exchange's fee.
The book, for a market order. You, for a limit, until it expires.
The thin book. A limit that never fills also stops you, by doing nothing.
Check yourself
Will a market order always fill at the last price?
No. It fills against whatever is offered, which can be worse.
After this you can choose whether you need a fill now or a price, and look at the size on the book.