Js Arrays — Free Javascript Tutorial

TL;DR: Learn Js Arrays in Javascript with a free, beginner-friendly tutorial, examples and practice for Indian students on Syllab.in.

Js Arrays in Javascript

An array is an ordered list of values stored in a single variable. Arrays in JavaScript are zero-indexed and can hold mixed types (numbers, strings, objects, other arrays).

Essential array methods: push/pop (end), unshift/shift (start), splice (middle), slice (extract), indexOf/includes (find), sort, reverse. These modify or query the array.

Functional methods: map() transforms each item, filter() keeps matching items, reduce() accumulates to one value, forEach() runs a function on each item. These are essential for modern JS development.

const arr = [1, 2, 3];
arr.push(4);          // add to end
arr.pop();            // remove from end
arr.includes(2);      // → true
arr.map(x => x*2);   // → [2,4,6]
arr.filter(x => x>1); // → [2,3]

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