On the screen you're looking at shows all the folders on the device Google Photos has identified as having images. It does this so that it can back up images from these folders if you choose to. If you installed another app, like Light Photo Editing, it would then show a folder for Light.
Do you have an app like FourSquare or Swarm on your device? They create check-ins at places you visit and allow you to leave reviews and photos if you take any of the place to share with a community. As B. Diddy asked, if there are any photos in there they should make the association of which app they came from pretty clear. I don't believe Google Photos displays folders that don't have pics or vids.
Also be aware that if you do get any new apps or begin taking pics or vids in an app you've not done that before Google Photos will ask in the notifications if you want to include this new Folder in your automatic backups and the folder will appear on this screen anytime you view it as a possible auto backup location.