For rendering PDFs, it uses the MuPDF library.

Sumatra has a minimalist design, with its simplicity attained at the cost of extensive features. It is developed exclusively for Microsoft Windows. If Ghostscript is installed, it supports PostScript files. Sumatra PDF is a free and open-source document viewer that supports many document formats including: Portable Document Format (PDF), Microsoft Compiled HTML Help (CHM), DjVu, EPUB, FictionBook (FB2), MOBI, PRC, Open XML Paper Specification (OpenXPS, OXPS, XPS), and Comic Book Archive file (CB7, CBR, CBT, CBZ). Since SumatraPDF offers all the necessary elements for the simple act of viewing a PDF file and is very easy to play with, we strongly recommend this tool to all users.The program uses a low-to-moderate amount of system resources and comes with a comprehensive user manual.In the “Options” menu, you can select the default layout and zoom, disable the options to show the bookmarks sidebar when available, remember current settings for each document, automatically check for updates and remember opened files, as well as make SumatraPDF your default PDF reader.Furthermore, you can change the interface language (there are numerous options to choose from), use a search function, print the document, use keyboard shortcuts and command-line arguments.In addition, you can rotate the page left or right, go to a particular page number, zoom in and out (up to 6400%) as well as create a favorites list.Thus, you can view document properties (file path, date of creation, application, PDF producer and version, file size, number of pages, page size), as well as change the view to facing, book, presentation, full screen, and others.You can import a document by using the file browser or drag-and-drop support. The user interface of the program consists of a plain window in which navigating is done seamlessly.

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