$v = "something";
$ref1 = \$v;
$ref2 = \$v;
# both $ref1 and $ref2 point to the same variable.

# change the value
$v = "something else"; # both $ref1 and $ref2 will point to the changed value

$v2 = "new value";
$ref1 = \v2; # $ref2 now points to a new variable
# $ref2 will continue to point to $v