GMail Drive creates a virtual filesystem on top of your Google GMail account and enables you to save and retrieve files stored on your GMail account directly from inside Windows Explorer. GMail Drive literally adds a new drive to your computer under the My Computer folder, where you can create new folders, copy and drag'n'drop files to.
Ever since Google started to offer users a GMail e-mail account, which includes storage space of a 1000 megabytes, you have had plenty of storage space but not a lot to fill it up with. With GMail Drive you can easily copy files to your GMail account and retrieve them again.
When you create a new file using GMail Drive, it generates an e-mail and posts it to your account.