The most obvious feature of Forth is the stack. When you type in a
number, it is pushed on the stack. You can display the contents of the
stack with .s.
.s displays the top-of-stack to the right, i.e., the numbers
appear in .s output as they appeared in the input.
You can print the top element of the stack with ..
In general, words consume their stack arguments (.s is an
exception).
Assignment: What does the stack contain after
5 6 7 .?