Day 1: "this", Closures & Hoisting

Daily Objective

Master the internal execution mechanisms of JavaScript: closures, hoisting, and the this keyword.

1. Closures

A closure is a function that retains access to its lexical scope even when executed outside that scope:

function createCounter() {
  let count = 0;
  return function() {
    count++;
    return count;
  };
}
const counter = createCounter();
console.log(counter()); // 1
console.log(counter()); // 2

Daily Hands-on Practice (70%)

1. Create a function generator producing custom multiplier functions using closures (double = createMultiplier(2)).