“These come in a variety of file formats; besides its own native file format of Kindle (.azw) files, your Kindle Fire HDX will also read books in Adobe Acrobat (.PDF) format, in MobiPocket (.MOBI) format, or in plain text (.TXT)… — Edward Jones Copy Share Image
“You can send Microsoft Word (DOC, DOCX), PDF, HTML, TXT, RTF, JPEG, GIF, PNG, BMP, PRC, and MOBI files to your Kindle and read them in Kindle format.” — Amazon Copy Share Image
