* Top: idicates a bestseller. If you want the 'Bestseller' tag to work properly, you need to change the status of shipped orders to 'Shipped'. The count of the bestselling products can be set in the plugin parameters.

* New: indicates a new product. A product stays new for a number of defined days. This can be set in the plugin parameters.

* Discount: indicates a discounted product

* Featured: idnicates a featured product. You have to have the "Featured" checkbox in the administration checked

That's it: it's a very simple way how to display product labels.