Pending orders act like limit orders or stop orders, depending on the price you submit. They work in both directions.
To submit a pending order:
Enter an Amount in the sidebar.
Click on Advanced, then set a Price for your order.
Click on Buy or Sell to submit your order.
To cancel a pending order, click on the X next to it in the Orders panel.
Keep in mind
Buy orders are triggered by the ask price and sell orders are triggered at the bid price.