At the start of the game you will discover you are equipped with an empty bag. A bag is a place to carry items you come across or purchase in The Land. If you left click on an item in a bag you can drag and drop it. Right click on useable items in the bag to use or equip them.

If you are trading with an NPC then right clicking will cause you to sell the item. If you are trading with other players, right clicking will move the item to an open trading window.

You can equip two extra bags besides the one you are given at the start of the game. Clicking on the icon at the top of the bag window will open the corresponding bag.

If you wish to move an item from one bag to another, then simply drag the item over the icon of the other bag. The bag will automatically open.