Handle in Windows

Handle is actually a pointer pointing to something in the memory space of the operating system. It cannot be accessed directly. YourProgramIt cannot be used directly to maintain system integrity and security.

The difference between a GDI object and a core object is that a GDI object has a single owner, either a process or a thread. The core object can have more than one owner, or even cross-process. To keep track of every owner, the core object uses a reference count to record how many handles correspond to this object. Reference counting is also a technology used by the COM interface!