JS Closures & Lexical Scope

A closure is the combination of a function bundled together with references to its surrounding state (lexical environment).

1. Lexical Scope Example

function outer() {
  const secret = 'encrypted-key';
  function inner() {
    console.log(secret); // Accesses parent scope variable!
  }
  return inner;
}
const getSecret = outer();
getSecret(); // Prints 'encrypted-key'