Dec 8, 2025 · The Map object holds key-value pairs and remembers the original insertion order of the keys. Any value (both objects and primitive values) may be used as either a key or a value.

A JavaScript Map is an object that can store collections of key-value pairs, similar to a dictionary in other programming languages. Maps differ from standard objects in that keys can be of any data type.

Feb 11, 2013 · The purpose of the function is to take an object and modify the original contents of the object using a method available to all objects (objects and arrays alike) without returning an array.

This tutorial introduces you to the JavaScript Map object and shows you how to manipulate maps effectively.

Sep 23, 2025 · A JavaScript Map holds key-value pairs and similar to Hash Map or Dictionary in other languages. Preserves the original insertion order. Supports any type, including objects and …

A Map is a built in object that holds key-value pairs. It can hold a key of any data type unlike in plain objects. It maintains the insertion order and provides helpers to manage key-value pairs.

Feb 21, 2024 · Map and Set are two JavaScript data structures you can use to store a collection of values, similar to Objects and Arrays. They are specialized data structures that can help you store …

Feb 6, 2025 · A comprehensive guide to the JavaScript Map object, covering its properties, methods, and practical usage with clear examples.

Nov 14, 2022 · If we have a plain object, and we’d like to create a Map from it, then we can use built-in method Object.entries (obj) that returns an array of key/value pairs for an object exactly in that format.

Jul 12, 2025 · For read heavy operations where strings are keys, Objects provide better performance. Object allows only Strings and Symbols as keys, but Map maintains key order and allows any data …