Gathering is just as it sounds. By clicking on items, you will start to gather an ingredient to be used in your crafting or trading.
Currently, there are 3 types of gathering methods and requirements. For example, we will use 3 products as example.
Reed
This item is a simple gatherable which when you walk up to it and click on it, you will begin to gather it. It will take a few seconds, and you will receive some reed into your virtual inventory.
Clay Mound
This item, if you walk up to it and click it, it will tell you that it requies a tool. In this case, you will require a small basket which is crafted at the Basket Weaving station. Without a small basket on you, you cannot continue to gather it.
Water
Walking up to a water source, the same thing will happen as the Clay Mound. It will tell you that you require a Clay Jar which are crafted in the Pottery Station, but instead of stopping and failing there, it will allow you to consume the water directly from harvest. You will not place it into your virtual inventory without the required tool, but you will consume the water to quench some of your thirst.
Items will vanish after being harvested and return after a respawn timer. Some items are set by the sim owner to respawn in certain locations around their sim, but not always in the same spot, so happy hunting!
Watch this video to see these three gatherables in process: