In an operating system, a process is:

Concept

An operating system distinguishes a passive program from an active execution context. A process is the dynamic context created while program instructions run; it carries current CPU state, memory references, and allocated resources.

Application

A program in execution has exactly this active context: the operating system tracks its program counter, registers, scheduling state, and resources while the instructions are being carried out.

Contrast

• A program written in a high-level language is source code that may later be translated or interpreted.

• The contents of main memory are a collection of stored instructions and data, potentially belonging to several execution contexts.

• A job in secondary memory is submitted work awaiting admission or loading and does not yet carry an active CPU context.

Cross-check

The same program can be launched more than once, producing separate contexts with different program counters and resource states. This confirms that the dynamic entity, rather than the passive code alone, is the process.

Therefore, a process is a program in execution.