Taken from Save, edit & share Microsoft Office files, specifically from the following section:
You can use Microsoft Office files in Google Drive in three ways on your computer:
- From web browsers or with sync clients
- Use the plugin with your Microsoft Office programs
- Upload your files to drive.google.com and use Office Compatibility Mode (OCM)
To sync files directly from your computer to Google Drive, download Google Drive for Mac or PC.
NOTE: The supported features of OCM are very limited.