First, we must understand that we have adopted a matching trading model. In other words, the transaction can only be carried out when the buyer and the seller provide the same price.
Let us give an example here. Please see the picture below:
From the picture, we can see that the latest selling price of bitcoin in the red selling book is 63014.60 $, the latest buying price of bitcoin in the green buying book is 62780.69 $, and the market price is 62888.82 $.
If the user wants to trade as soon as possible, he must match the last price in the order book. In other words, if the user wants to sell his Bitcoin as soon as possible, he must directly accept the last purchase order at the price of 62780.69 $. If he wants to buy, then he must accept the last sell order at 63014.60 $.
If the user sets the limit price to buy or sell, the user must wait until the last price reaches the limit price, otherwise the order will not be traded.