A good answer might be:

• formal parameter --- the identifier used in a method to stand for the value that is passed into the method by a caller.
• actual parameter --- the actual value that is passed into the method by a caller.

The type of parameter passing that Java uses is called call by value. Some programming languges use other methods of parameter passing, and some give the programmer a choice amoung several ways to pass parameters. The call by value method that Java uses is the most common method in modern languages and is the easiest and safest.

This is how call by value works:

1. When the caller invokes a method, the caller provides a list of values (the actual parameters) in the parameter list.
2. When the invoked method starts up these values are "bound" to a list of names (the formal parameters.)
3. The invoked method uses these names to "stand for" the actual values.
4. The invoked method cannot use the parameters to send a value back to the caller.

QUESTION 2:

(Review:) What is a primitive data type?