mobile downloads.lrdata vs lightroom cc

I seem to have around 400gbs worth of files stored in the cloud, but on my actual desktop within the lightroom folder I actually have two sub-folders (mobile downloads.lrdata and lightroom cc) that each individually contain about this amount. Within the mobile downloads folder are two folders with the names of my two main computers and 170/230gbs respectively.

What's going on here? Are they duplicating and wasting a ton of HD space? How do I free up some room?