LibreOffice - Free office suite, open source, and compatible with .doc, .docx, .xls, .xlsx, .ppt, .pptx files. Updated regularly – download for free. Originally based on OpenOffice.org.
Apache OpenOffice - Apache OpenOffice is an open source, office document productivity suite.
WPS Office - Would you need Office Word, Excel or PowerPoint for Home, business or School? WPS.com would give you right version for you.
Caret - Better Markdown Editor for Mac / Windows / Linux
ONLYOFFICE - ONLYOFFICE is a complete office and productivity suite.
Scribes - A text editor for GNOME that combines simplicity with power.