Final answer:
The process control block (PCB) is a data structure used by the operating system to manage and control processes. It enables the OS to support multiple processes and provide multiprocessing.
Step-by-step explanation:
The process control block (PCB) is a data structure used by the operating system to manage and control processes. It contains important information about a process, such as its process ID, program counter, registers, and memory allocation details.
The PCB is essential for supporting multiple processes and enabling multiprocessing. It allows the operating system to switch between different processes, allocate system resources, and manage their execution.
For example, when a context switch occurs, the operating system saves the current process's state in its PCB and loads the state of the next process from its PCB. This allows the operating system to efficiently manage and switch between multiple processes.
The OS uses this structure to manage processes efficiently and ensure that the system's performance and stability are maintained during multitasking and multiprocessing operations.