Arrays & Methods

Arrays store sequences of items. The magic of JavaScript: array contents can even be a mix of various unrelated data types!

Declaration

main.js

const fruits = ["Apple", "Banana", "Cherry"];
console.log(fruits[0]); // Output: Apple

Modern Array Methods

push(): Adds an item at the very end.

map(): Transforms/maps each array cell to a new cell arrangement (the heart of HTML mapping logic in ReactJS).

filter(): Removes elements if the condition is false.

main.js

const numbers = [1, 2, 3, 4, 5];
// Map: Multiply all numbers in the array by two
const doubled = numbers.map(num => num * 2);
console.log(doubled); // [2,4,6,8,10]
// Filter: Extract all even numbers
const evens = numbers.filter(num => num % 2 === 0);
console.log(evens); // [2,4]