Saving of files
I am new to Zotero and am trying to organize my downloaded files...but I am a bit confused about how things are saved and copied. I can see the same items in "My library" as well as in the sub-collections of "My Library." Is this how they are stored or are they duplicates? Ultimately I would like for "My Library" to show that there are no files, all files having been moved to sub-folders. Is this possible, or do items show up in both places?
https://www.zotero.org/support/collections_and_tags#the_zotero_collections_model
My Library will always show all your items. You can use the Unfiled Items collection to verify that everything has been added to a collection.