Glossary term
What is GIL (Global Interpreter Lock)?
GIL stands for Global Interpreter Lock.
Lets only one thread run Python code at a time (in standard CPython). Example: Python uses multiple processes for CPU-heavy work.
Learn it properly · System DesignLesson 4: Processes, Threads & Concurrency for Backend EngineersMost backend work is waiting. How one server juggles thousands of requests — processes, threads, event loops and lightweight threads — and the race conditions, deadlocks and pool limits that appear the moment it does.