Error handling differs between module systems: 1) CommonJS throws synchronous errors that can be caught with try-catch, 2) ES Modules throw errors during the asynchronous loading phase, 3) CommonJS errors are immediately available when require() fails, 4) ES Module errors must be handled through module loading error events or import() promises, 5) This affects how applications can handle module loading failures, 6) ES Modules' error handling is more complex but provides better integration with async patterns, 7) These differences impact error handling strategies and application reliability.