Well, here's what the perlop manpage says:

As more readable alternatives to && and || when used for control flow, Perl provides and and or operators (see below). The short-circuit behavior is identical. The precedence of ``and'' and ``or'' is much lower, however, so that you can safely use them after a list operator without the need for parentheses:

    unlink "alpha", "beta", "gamma"
            or gripe(), next LINE;
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With the C-style operators that would have been written like this:

    unlink("alpha", "beta", "gamma")
            || (gripe(), next LINE);
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So in other words, if you said this:

unlink "alpha", "beta", "gamma" || gripe();
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the third argument to unlink would be "gamma" || gripe(); that is, always "gamma" and gripe() would never be evaluated.

'or' is smarter than that. Look at C-style Logical Or and Logical or and Exclusive or on the perlop manpage. It talks a bit about why this happens.

local $_ = "0A72656B636148206C72655020726568746F6E41207473754A";
while(s/..$//) { print chr(hex($&)) }
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