S-expresions are really just a way of representing a tree of data (in Lisp code, the S-expression literally represents the abstract syntax tree that is used for

S-expresions are really just a way of representing a tree of data (in Lisp code, the S-expression literally represents the abstract syntax tree that is used for the code). Take the JSON example: { "IDs": [116, 943, 234, 38793], "Settings": { "Aperture": 2.8, "Shutter speed": "1/250" } } You could rewrite this as an S-expression as: ((IDs (116 943 234 3879)) (Settings (Aperture 2.8) ("Shutter Speed" "1/250")))