The GIL is a mutex that protects access to Python objects, preventing multiple threads from executing Python bytecode simultaneously, which can limit concurrency.

The Global Interpreter Lock (GIL) is a mechanism that prevents multiple native threads from executing Python bytecode at once. This means that in a multi-threaded Python program, only one thread can execute Python code at a time, even on multi-core processors. The GIL simplifies memory management and avoids race conditions, but it can limit the performance benefits of multithreading for CPU-bound tasks. For I/O-bound tasks, such as network requests or file operations, multithreading can still be beneficial, as threads can switch while waiting for I/O. However, for CPU-bound tasks, consider using multiprocessing, which spawns separate processes, each with its own Python interpreter and memory space. By understanding the implications of the GIL, you can make informed decisions about concurrency in your Python applications.