How can I debug a Perl script?

Question

When I run a Perl script, how can I debug it? For example, in ksh I add the -x flag. But how I do the same in Perl?

Answer 1

The most effective debugging tool is still careful thought, coupled with judiciously placed print statements.

Brian Kernighan, "Unix for Beginners" (1979)

(And enhancing print statements with Data::Dumper)