sub rndStr{
	# When an array is interpolated in a string $" is used to seperate the values 
	# By setting it (locally) to '', we ensure that the string doesn't have spaces or 
	# anything else inserted between the characters.
	local $" = ''; 
	
	my ( $len, @chars_to_pick_from) = @_;
	
	# @picks will end up with as many random values as requested.
	my @picks = map{ 
					# Generate random numbers bewteen 0 and 
					# the number of chars supplied to pick from
                    rand $#chars_to_pick_from
                    
                    # do it as many times as request
                   } 1 .. $length;
                   
    # Using an array slice interpolated in quotes to construct the string
    # @picks contains the random indices, the slice picks them out of the
    # array of choices past in. The resultant string is returned as a scalar.
    "@chars_to_pick_from[@picks]"; 
}