What is the difference between process.exit() and throwing an uncaught exception?

process.exit(code) immediately terminates the Node.js process with the given exit code (0 = success, non-zero = error). It bypasses the normal event loop drain — pending callbacks, I/O operations, and promises are abandoned. Before calling process.exit(), emit a "beforeExit" event yourself or use process.exitCode property (lets the event loop drain naturally first). Use process.exit() explicitly only in CLI tools after completing work, or in fatal error handlers after cleanup. Throwing an uncaught exception (an exception not caught by any try/catch) triggers the uncaughtException event on process. If no listener is registered, Node.js prints the stack trace and exits with code 1. If you register a listener, the process can continue (but the application is in an undefined state — this is dangerous). The recommended pattern: listen to uncaughtException and unhandledRejection for logging/cleanup, then call process.exit(1). Do not attempt to continue after uncaught exceptions. For Promise rejections: unhandledRejection will cause process exit by default in Node.js 15+.