The words subroutine and function are often used
interchangably in perl. (Even
"not really a function"
was that it is very
unlike the functions you define in your code, which have
a symbol table entry and thus are associated with
a package, can have coderefs be taken
of them, and be aliased to other names at the symbol table
entry, or imported into other packages, in addition to being callable by the
syntax.