suppose that you have the following code snippet :
From the code snippet above, the value 1 passed from the main method to the doIt() method is the actual parameter, and the toDo parameter in the doIt() mrthod is the formal parameter, sometimes it's also called the dummy parameter.
Note that one reply above used "parameter" and the other used "argument" for both actual and formal. Google up on the terms and see if you think either or both were correct. Sometimes you'll see parameter used for the formal and argument used for the actual.
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The distinction is arguably subtle (no pun intended), and I have to admit I'm not as careful with these words as I should be. Interestingly, Wikipedia redirects "argument" to the entry for "parameter," which discusses both words.
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