Polyfill

Definitions

1. A piece of JavaScript code that implements a modern web API or language feature in older browsers that don't natively support it, allowing developers to use newer standards while maintaining backward compatibility. core-js is the most widely used polyfill library.

   In plain English: Code that teaches older web browsers a new trick they don't know yet, so websites using modern features still work on them.

   Example: "We added a polyfill for Array.prototype.at() so the app works in Safari 14, which doesn't support it natively."

Related Terms

• Callback Hell
• Transpiler
• Deno
• Bun
• JavaScript Module
• Module Bundler
• Module System
• Pnpm
• URI
• URL Parser
• XHTML