Multi-platform, fast and packed with features, Okular allows you to read PDF documents, comics and EPub books, browse images, visualize Markdown documents, and much more. Illustration from David Revoy CC-BY-SA-4.0 Support for Many FormatsOkular supports many formats, including PDF, EPub, DjVU and MD for documents; JPEG, PNG, GIF, Tiff, WebP for images; CBR and CBZ for comics; and many, many more.