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Google Drive for Desktop works by creating very small files in a secured Google Drive disk image file on your computer that is mounted like a disk drive to allow you to quickly access the contents of your cloud-based Google Drive from within the native infrastructure of your Windows or Mac computer. Google Drive for Desktop maintains a curated number of those files locally on your machine, based on frequency of use and / or whether you specify that you want a local copyThe disk image file contains a complete manifest (a list) of all of your Google Drive files, as well as the complete contents of a subset of those files that have been most recently accessed, or specifically tagged for local storage. With Google Drive for Desktop, you can make selected files or folders 'Available offline' to sync them to your computer.
The files are stored inside an encrypted disk image file that can only be accessed by your Google user account. Depending on your selections, you may not be able to access a portion of the files without an internet connection. The upside is that it will only take up a very small amount of space on your local storage (compared to your whole Google Drive)fraction of the size of your entire Google Drive, and allow you to search for and find files simultaneously both on your Google Drive and in local storage through your operating system. As well, the entire contents of your Google Drive are not synchronized each time you log in, but rather only the small sub-set of recently-used or locally-stored files, speeding up the process of synchronization (which happens at login) significantly in the case of folks with lots of shared files. Google Drive for Desktop also labels each file in your system as to it's status -- a cloud icon for online files, and a green check mark for locally-stored ones.
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