Store and access ANY kind of file from anywhere. Share files (view, comment, edit) with anyone. MUCH better than an X drive :-)
Check your Drive settings to control whether you want Drive to convert common file types like MS Word, Powerpoint, Excel to Google format (Docs, Slides, Sheets) when you upload them. This makes them much more collaborative documents. You can open unconverted versions of these files and make minor adjustments, but you won't have all the collaborative and editing features.