Use of caller in Perl

Caller or Caller Expr
Returns the context of the current subroutine call. In scalar context, returns the caller's package name if there is a caller, that is, if we're in a subroutine or eval or require, and the undefined value otherwise. In list context, returns
#      0            1            2
($package, $filename, $line ) = caller;


With EXPR, it returns some extra information that the debugger uses to print a stack trace. The value of EXPR indicates how many call frames to go back before the current one
# 0                       1       2           3             4
($package, $filename, $line, $subroutine, $hasargs,

 #    5                6              7             8           9           10
$wantarray, $evaltext, $is_require, $hints, $bitmask, $hinthash)
= caller($i);

(caller 1)[3] will give the name of the calling subroutine.
($package, $filename, $line ) = caller; or

($package, $filename, $line ) = caller 1; # Both of these are equivalent

@caller = caller 0; #will return whole information about the calling subroutine