One could look at it as two orthogonal questions, yielding four classes of language. Question 1: does the runtime receive interpretation semantics of values fro

One could look at it as two orthogonal questions, yielding four classes of language. Question 1: does the runtime receive interpretation semantics of values from the compiler (yes = "dynamic", no = "static")? Question 2: does the enforcer of interpretation semantics ("types") do so liberally or conservatively (liberally = "weak", conservatively="strong")? So, dynamic strong would be Lisp[0], dynamic weak would be PHP, static strong would be Haskell, static weak would be C. I suppose there's even a fifth option of "no interpretation semantics to begin with", which would be something like Forth. [0] As you seem to allude: a dynamic language makes this question more tricky.