How to define a website visitor is returning or new

/core/Tracker/Visit.php protected function recognizeTheVisitor()

$timeLookBack = date(‘Y-m-d H:i:s’, $this->getCurrentTimestamp() - self::TIME_IN_PAST_TO_SEARCH_FOR_VISITOR);

	$where = "visit_last_action_time >= ?
				AND idsite = ?
				AND config_id = ?";
	$bindSql = array( $timeLookBack, $this->idsite, $configId);

and TIME_IN_PAST_TO_SEARCH_FOR_VISITOR = 86400 //24 hours
the code seem that if the visitor in 24 hours visit the the same idsite website is returning visitor
it that right?


doesn’t this mean that if a user visits the site, and visits it again after more than 24 hours it will be counted as new unique visitor?

Only if he didn’t have the Piwik cookie when he returns to the site