The HyperTalk interpreter used in earlier versions of HyperCard has been replaced by a compiler—so HyperTalk scripts now run faster.
HyperTalk compiles a handler automatically on first execution and stores the compiled code in RAM. The compiled code is then available for subsequent executions of the handler as long as the memory it occupies is not required for another purpose. When you quit HyperCard, the compiled code is flushed from memory; it is not stored on disk.