Difference between program & operating system process:
The process may be called the active state of a program. It also gives the status of given task mentioned in that particular program, it provides the information to main memory about the task's state and other details, for example the position it has executed up-to that instance. It keeps track of the status of registers and instances of the resources it hold and required resources, what cost it incures on the cpu after it is done with its work.
Program is an active entity, it can been seen as the overall information on what has to be done with CPU and other resources which are likely to be needed or liable to complete that given task. In some cases it simply is a combination of Lite weight processes( known as threads) and thick weight processes as we may require to run various modules of different programs in some single program. Thus the process is similer to a platform on CPU for executing various tasks of given program and part of the main set of process.