What Is an Array?

An array stores multiple values in a single variable. Arrays use square brackets [ ].

let cars = ["Audi", "BMW", "Subaru"];
console.log(cars);
      

Accessing Items

console.log(cars[0]); // Audi
console.log(cars[1]); // BMW
      

Modifying Array Items

cars[1] = "Mercedes";
      

Array Length

console.log(cars.length);
      

Adding Items

Push (adds to end)

cars.push("Toyota");
      

Unshift (adds to start)

cars.unshift("Volvo");
      

Removing Items

Pop (removes last)

cars.pop();
      

Shift (removes first)

cars.shift();
      

Looping Through an Array

Classic For Loop

for (let i = 0; i < cars.length; i++) {
  console.log(cars[i]);
}
      

For…of Loop

for (let brand of cars) {
  console.log(brand);
}
      

forEach

cars.forEach(car => {
  console.log(car);
});
      

Joining Array Elements

let text = cars.join(", ");
console.log(text);
      

Checking If It's an Array

console.log(Array.isArray(cars)); // true
      

Nested Arrays

let matrix = [
  [1, 2],
  [3, 4]
];

console.log(matrix[1][0]); // 3
      

Why Arrays Matter

• Store large sets of data easily
• Simple to loop through
• Perfect for lists, tables, menus, grids, etc.
• Core part of JavaScript logic

What’s Next?

Next you’ll learn CSS animations and how to make your website feel alive and dynamic.