I tried to but I cannot find any information about it.
I can create CATEGORIEs, but I fail to find anything that I can understand that hints at subcategories.
It might,. as I said, be a problem ofd my dumbness or mail failiure to understand english, as English is noit my mother tongue specially technical English is sometimes a problem...
Easy, just name your category appropriately. For instance, if you have a category named 'Computers', to have a subcategory named Hardware just click on Add Category, and name it 'Computers/Hardware'.
You can have as many levels as you like 'Computers/Hardware/Video_Cards/Diamond' for instance, but just make sure you have the appropriate categories before hand (i.e. in the above example, you would need to have 'Computers', 'Computers/Hardware' and 'Computers/Hardware/Video_Cards' first.
I find it hard to believe you don't understand that, especially as your english seems pretty good to me.