i think of null as conveying: "this value was intentionally set to 'null' in contrast to undefined: 'this value is undefined (e.g. was never [correctly] set)

i think of null as conveying: "this value was intentionally set to 'null' in contrast to undefined: 'this value is undefined (e.g. was never [correctly] set)' Though this doesn't apply to dealing with unsanitized json parsing.