LibreOffice

LibreOffice is a cross-platform, open-source office software suite from The Document Foundation that offers word processing, spreadsheets, presentations, a drawing application that does 3D, a database front-end, and file compatibility with Microsoft Office and other formats. (See LibreOffice vs. Microsoft Office feature comparison for more details.)
  The latest LibreOffice version is “a feature-rich major release of the LibreOffice 6 family with better performance, a large number of new and improved features, and enhanced interoperability with proprietary document formats.” (See also: LibreOffice security updates.)
  LibreOffice 6.3.2 is a free, donationware download for OS X 10.10 and up (with a separately installed Java Runtime Environment (JRE) required for some features, notably the database front-end, Base), and it runs on Windows and Linux, as well.
  LibreOffice 6.2.7 is a “more mature version” recommended for enterprise, corporate environments and more conservative users who don’t need all the very latest features.
  LibreOffice Online is available as a Docker image, “which provides basic collaborative editing of documents in a browser by re-using the LibreOffice core; rendering fidelity should be excellent, and interoperability match that of LibreOffice” for those willing to set up the necessary host platform.