What is in 'Guest' folders?

I am trying to clean out clutter from my computer and came upon the 'Users' folder in the hard drive. Within the Users folder there are three folders: Guest then me (my name and icon of a house) then Shared. I clicked on Guest folder and there are several folders with seemingly generic names. (See screenshot). I tried opening them and it says I do not have permission to open them. What's up with that? I'm the only one who uses this computer. What is in them and why can't I access them and can I delete them? Thank you.

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