In a nutshell (eli5) swap is sorta "very slow ram" which is actually just a section of your hard drive /SSD/some other bizarre medium. It is generally used to temporarily store information that might be needed later but would waste valuable "fast ram" which is your actual ram sticks.

What's going on here is this user mounted Google drive in a way that the operating system can interact more directly with it, and it appears to have a set amount of space. Because we've mounted Google Drive we can tell our operating system to use it as swap....very very slow silly swap, but swap nonetheless.

So that's exactly what they did, they told the operating system to set aside X amount of Google Drive for swap, and when looking at the resource monitor we can see the "swap" appears as "more ram".

Hope that helps, please ask if I confused you :)