Sumatra PDF Overview
SumatraPDF is a free, open-source document reader for Windows, prized for being extremely fast and lightweight. Despite its small size, it opens not just PDF but also ePub, MOBI, XPS, DjVu, CHM, and comic-book (CBZ/CBR) files, which makes it a handy all-round reader. It starts almost instantly, has a clean and minimal interface, supports keyboard navigation, and is available as a portable single executable that needs no installation. It focuses on reading rather than editing, which is exactly why many users keep it as a fast, no-clutter alternative to heavier PDF software. Its full installer holds the complete application, so it sets up on a machine with no internet connection. It also remembers your reading position per document and supports SyncTeX for LaTeX users, jumping between source and rendered output. Download Sumatra PDF from Krzysztof Kowalczyk's official source, linked here.