This is a picture of paper sizes as compared to a human being who will presumably be reading or writing on them. It also has an oddly late-70s/early-80s postmodern art feel, as if it was a photo-collage mural by Gilbert & George. The bright colors, the little peephole in the middle of A7, the socks….
I found this among the exploded computers and motor parts in the “Technical Drawings” category of Wikimedia Commons.