On the Web, Google Drive is mostly used as a competitor to Microsoft Office. You get apps for word processing, spreadsheets, and slides. On a desktop computer, the Drive app takes on a different form—it's a Dropbox competitor, syncing your files to the cloud from a special folder. This week, Google announced the Drive desktop app is changing; it's not even called "Drive" anymore. Now this app is called "Google Backup and Sync," and it gains a few new features while merging with the Google Photos Syncing app.
While it isn't happening by default yet, it looks like Google is planning on automatically upgrading users of the Drive and Photos syncing apps to the new unified app. It's clearly the new version of the Drive app (just version 3.x instead of 2.x), and running the installer will do an in-place upgrade of the prior app. On the first launch, a dialog box explains a bit about the transition.