What are the main differences between using threads and processes when executing programs?

The main differences between threads and processes are as follows:

• Isolation: Processes have their own address space, meaning each process's memory is isolated. Threads within the same process share a common memory.

• Resources: Creating and switching between processes requires more resources and time than between threads.

• Data exchange: Threads can easily exchange data through shared memory, whereas processes require inter-process communication (IPC), such as channels, queues, or sockets.

• Security: Process isolation enhances security and stability, as a failure in one process does not directly affect others. Threads are more tightly coupled, and an error in one thread can lead to the failure of the entire process.

In Python, due to the GIL (Global Interpreter Lock), multithreading is limited in terms of parallel execution of CPU-bound tasks, so for such tasks, multiprocessing is often used.

Example of creating a thread and a process in Python:

import threading
import multiprocessing

def worker():
    print('Working')

# Thread
thread = threading.Thread(target=worker)
thread.start()
thread.join()

# Process
process = multiprocessing.Process(target=worker)
process.start()
process.join()