Google Drive offers file stream for enterprise users who want direct access to their Drive content from their desktop. It's a feature that's similar to the "sync" feature, but instead of keeping a local copy of your Drive content on your computer, file stream provides a "virtual" Drive that you can access from your computer just like any other drive.
There are a few benefits of using file stream over the "sync" feature:
File stream doesn't take up any local storage on your computer - since it's a virtual Drive, the content is stored entirely on Google's servers. This can be a big advantage if you have a limited amount of storage on your computer.
File stream provides a higher level of security - since the content is stored on Google's servers, it's protected by their world-class security infrastructure.
File stream is faster - since the content is stored on Google's servers, you can access it more quickly than if it was stored locally.
If you're an enterprise user and you're interested in using file stream, talk to your Google Drive administrator.