zend framework - What do two colons mean in PHP?

I don't know what it's doing when we have this situation:

Foo::Bar

It looks like a path.

Answer

That's (generally) for accessing a static method or property in a class. It's called the scope resolution operator, or Paamayim Nekudotayim (which leads to some amazingly confusing error messages!). See http://www.php.net/manual/en/language.oop5.paamayim-nekudotayim.php.