Passing Arguments between Program Modules
Data is typically
“owned” by the function that creates it.
Other functions
cannot “see” that data unless it is somehow “shared.”
Data that exists
in one module, and is needed by another module, must be “passed”
to the other module in an “argument list,” which is a list of data items.
“Passing”
arguments is how modules communicate between themselves,
allowing them to share data to perform certain tasks.
If a function
multiplies two numbers,
it must be given the numbers in order to perform the multiplication.
The module that is
asking the other do the math,
must provide the data so the other module can do it.