# On-chain Based Trading

Once the pre-sale period ends, you can continue trading on the order-book. Order-book trading is executed through the matching of buy and sell orders, allowing users to sell the DNA they have purchased or buy new quantities.

The order methods provided by Alt.town are as follows:

## **Limit Order**

* A limit order is a type of order submitted by a user who manually enters the price and quantity of DNA they wish to buy or sell.
* This order type is used when price is a priority, ensuring that the order will not be executed at a price higher than the specified buy price or lower than the specified sell price.
* If a sell order is place at a price lower than the current market price or a buy order is placed at a price higher than the current market price, it will be executed at the market price.
* Even if the specified price is reached, limit orders may not be executed due to the order method execution mechanism (price > time priority).

{% hint style="danger" %}
Depending on trade execution conditions, the pending order may not be fully executed.
{% endhint %}

## **Market Order**

* A market order is an order submitted without specifying a price.
* This order method is used when you want to execute a trade quickly. By setting only the order amount for a buy order or the order quantity for a sell order, the trade will be executed immediately at the market price.
  * Buy Order: If users set only the order amount, it will be immediately executed at the lowest price among the current ask prices.
  * Sell Order: If users set only the order quantity, it will be immediately executed at the highest price among the current bid prices.
* When a market order is placed, it will be executed sequentially, starting from the most favorable price (best bid/ask).

{% hint style="danger" %}
Orders may be rejected for the protection of users’ assets. Please refer to the order rejection criteria if your market order is rejected.
{% endhint %}


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