ECMAScript Modules (ESM), the official standard for JavaScript modules, revolutionizes how we structure and import JavaScript. ESM provides encapsulation of code into reusable modules and enjoys support from all major browsers.

Before ESM, JavaScript lacked a native module system, leading developers to use unofficial methods like CommonJS (CJS) and Asynchronous Module Definition (AMD). ESM introduced "static" imports and exports, which are analyzed at compile-time rather than at runtime, improving performance and tooling capabilities.

Modern browsers, including Chrome, Firefox, Safari, and Edge, fully support ESM. This native support simplifies the development process and eliminates the need for transpiling tools like Babel or webpack, as demonstrated by tools like

ESM's adoption has led to significant impacts, such as improved performance from prefetching and pre-parsing of modules, better debugging from accurate source maps, elimination of browser transpiling, efficient loading due to dynamic imports, and cleaner, more maintainable codebases.

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