One might also note that arguments are the values that fill parmeters. So if we have

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foo("square", 3);
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sub foo{
  my ($shape, $size) = @_;
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$shape and $size function as parmeters that are filled with the arguments "square" and 3. Now, to be accurate, perl5 does not have true formal parameters as do many other languages including perl6. You can get the perl6 behavior using Perl6::Parameters, however. Anyway, in the general computer science nomenclature, arguments are passed to functions into parameters.

It seems that the terms are often used to mean the same thing, but that often rankles some language lawyers and other pendantic individuals.