Bests & Worsts Reviews from Amazon

I intended to use my Kindle as a convenient way to access and read more than a hundred different journal articles in several major subject areas. While I was uploading the material, and Kindle appeared on my computer desktop, I carefully created different folders and subfolders to organize the content for easy access. But when I tried to read my uploads, I soon discovered that the Kindle unit itself doesn't recognize or show any folders at all! As a result, all the many different documents ended up lumped together in one overly long and totally disorganized list. That's VERY unsatisfactory and negates any value the unit would have for uses other than reading one book at a time.