When you download Google Drive, you get additional Google apps whether you want them or not, at least on some platforms. For example, you can download Google Drive on a Windows computer only as part of a package that includes Google Sheets, Google Slides and Google Docs. On the iPad, you can limit your download to Google Drive.
Google Drive is available for Windows and Macintosh computers, Android and iOS phones and tablets. Google Drive is also available on the Web using nearly any Web browser.