OnlyOffice

OnlyOffice is a modern open source office suite for Windows XP/Vista/7/8/10/11 by the Russian company developed by Ascensio System SIA. This office suite provides a user-friendly, modern, and minimalist theme to suit any general audience. Many features expected in Microsoft Office are also present in Ascensio System SIA's software. From customizable fonts, margin customization, charts, lists, comments, custom templates, auto-save, file/document recovery, and other every day needs. Another feature that makes this software extraordinary is the availability of online collaboration.

Despite this suite's obscurity and holding less popularity than other suites, it is nevertheless extremely effective and optimized on even a Pentium M. It has been far my personal favorite.


Features:
**Lightweight office suite
**Compatible with doc, docx, pdf, docf, dotx, odt, rtf, txt, html, fb2, epub, and various documents
**Cross-compatibility with Microsoft documents
**Built-in file data recovery
**Connectivity to cloud storage
**View, edit, and collaborate on docs, sheets, slides
**Read PDFs and export/import to/from PDF
**Convert docs to Markdown and HTML
**Turn your textbooks into e-books
**Compare and review docs and track changes
**Leave comments and mentions
**Communicate via built-in chat or Telegram
**Make audio and video calls with Jitsi or Rainbow
**Open-source code available on GitHub
**Compliance with international security standards
**Three levels of encryption: at rest, in transit, end-to-end
**Secure access and monitoring tools
**Extra document permissions

Requirements:
Windows XP or later

Screenshots: