An application can obtain a handle to a process that can be used as a parameter to many process-information and control functions. You can use this handle to initialize a System.Threading.WaitHandle or to call native methods with platform invoke.

This process handle is private to an application--in other words, process handles cannot be shared. A process also has a process Process.Id which, unlike the Process.Handle, is unique and, therefore, valid throughout the system.

Only processes started through a call to Process.Start set the Process.Handle property of the corresponding System.Diagnostics.Process instances.