In-browser reading
Most purchases are meant to be read in the web reader. That experience can include rich layout, images, and navigation the author designed for the browser.
When an author attaches a PDF, you may download it from your book or library flow. PDFs are great for offline reading and printing; layout is fixed like a printed page.
Not the same as other stores
Girls in Cloud is not a Kindle or proprietary-device lock-in store. You buy here and access through this site (and any downloads the author enables).
My PDFs
My PDFs is for files you upload yourself—not a replacement for bookstore purchases. Use it for personal documents you want to read alongside your bought books.