Runtime (Browser Environment)


JavaScript alone = language

But it needs a runtime to run


Browser = Runtime

Browser gives:

  • DOM (Document Object Model)
  • APIs (fetch, setTimeout, etc.)
  • Event system


Example

console.log("Hello");

console.log() is NOT pure JS

It is provided by the browser runtime


Runtime Components

Includes:

  • Call Stack
  • Web APIs
  • Event Loop
  • Callback Queue


👉 You’ll learn these deeply later (advanced level)