To scale your application beyond the single-thread limit, you must master Node's concurrency modules.
1Worker Threads (The JS Way)
Workers are best for tasks written in JavaScript that require high CPU usage, like image processing or complex data sorting. Because they live in the same process, the overhead of creating them is relatively low.
2Child Processes (The OS Way)
Sometimes you need to run a Python script, an FFmpeg command, or an 'ls' command. The child_process module provides spawn, exec, and fork to interact with the underlying Operating System directly.
3Clustering: Auto-Scaling
Node's cluster module is a specific use case of child processes that allows you to spawn multiple instances of your server to handle traffic across all CPU cores. PM2 handles this automatically behind the scenes.
