What does the "menu" option do in content module?

What does this "menu" option do exactly?
The online help says:"Menu : By default, the links of a HikaShop content module will go to a page displaying the listing to sub elements (products or categories). This page won't have any content configuration attributed unless you choose here a HikaShop joomla menu here where you will be able to configure its options and thus add there a listing of products, etc."

Not sure what it means after reading it ten times.

The menu option is there for you to select the destination menu item when you click on a link of the module.
By default HikaShop creates a menu item for each module and selects it automatically in that option of the module so that it works.
But you can potentially change it.
If you're unsure and that everything is working properly regarding the module links, don't change that option.