Indeed. Pages 49 - 54 of PERL5 Pocket Reference - Johan Vromans lists every single one of them. $US 6.95 $CAN 9.95 ISBN 1-56592-495-9 ... I quote

@ARGV - Contains the command-line arguments for the script (not includ
+ing the command name [like in C], which is in $0).
[...]
$_ - Alternative: $ARG
The default input, output, and pattern-searching space.
[...]
$! - Alternative: $OS_ERROR, $ERRNO
Used in a numeric context, yields the current value of errno.  Used in
+ a string context, yields the corresponding error string.
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I hope you find that helpful.