What's the difference between 진짜 and 정말? I've heard both of them used to mean "really"

Question

What's the difference between 진짜 and 정말?  I've heard both of them used to mean "really"

Answer

There is not much difference between them. They are interchangeable. However, There are more meanings of  진짜, meaning "a genuine article, the real stuff" but 정말 truly, really, quite, indeed, very, and truth, reality, a fact.