It depends what you mean by "type theory", but you're right. See Pierce for a more practical introduction. "Proofs and Types" is more fundamental and focuses on

It depends what you mean by "type theory", but you're right. See Pierce for a more practical introduction. "Proofs and Types" is more fundamental and focuses on the interplay between the operational semantics of the underlying language and the structure of its type system (read as proofs of properties of programs written in the language).