So I've been reading through the book PHP Solutions, Dynamic Web Design Made Easy by David Powers. I read through the short section on Object Oriented PHP, and I am having a hard time grasping the idea of the -> operator. Can anyone try to give me a solid explanation on the -> operator in OOP PHP?

Example:

$westcost = new DateTimeZone('America/Los_Angeles');
$now->setTimezone($westcoast);

Also,a more general example:

$someObject->propertyName

Thanks