Java, as it is now, has two different types of data—primitives and objects. In the coming releases, there will be a new type that is called ValueType. For everyday programming, there should be no difference between objects and value types but under the hood they are really different. They are like objects but work as if they were primitives. The second part of the sentence means: they are effective. Other languages have this type of data handling, though they usually do not call them with this name.