What is the difference between static and stack data?

Depending on the use , Static data is data that cannot change it is Static so is usually set at the start of the program and cannot change,

In the Forth programming language the stack is the work area of memory you place data onto the stack to manipulate it (example Place 2 and 3 onto the stack, execute the + command removes the top 2 items off the stack adds them together and places the result back onto the stack.)