If you’re like me, you have a lot of ebooks on your Kindle. Some of them might be in different formats or from sites other than Amazon. There are a lot of tools to help you manage your ebook library. You might want to convert ebooks brought on older devices or other operating systems so you acn read them on your Kindle. Some even let you edit and create ebooks.
I use calibre to manage my library of ebooks. It’s a a free and open source program with a lot of useful features.