I suspect that one could produce a class that is not a type,
Say: has not a complete type definition. Think of type for example with the distinction of strings and numbers.
Types start from low level units. A class definition must know about strings and numbers, it inherits this knowledge from the syntax of language. Even an empty class must be constructed.
Types may be composed resp derived from other types. Any class finely will constitute a type composed by its body.
In case an definition may used for example equally for addition or string-concatenation, ambiguity constitutes a composed resp. derived type by themselves.
In general terms: the type tells the structure of arguments it receives alongside with the way, it deals with them.
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