Edit Microsoft Office files in Chrome and ChromeOS
Google Apps users can now edit Microsoft Word, Excel, and PowerPoint files directly from Google Drive, Gmail and the new Docs, Sheets and Slides home screens, without needing Microsoft Office. For ChromeOS users, there’s nothing to install, it just works. Chrome users for Mac and Windows can install the “Office Editing for Docs, Sheets & Slides” extension and you’re good to go.
More information:
Get the Office Editing for Docs, Sheets & Slides Chrome extension
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