---
title: "Kartik Kumar (@kartik210) | Hashnode"
description: "Grinding the Thoughts. Read the latest articles by Kartik Kumar on Hashnode."
url: "https://hashnode.com/@kartik210"
---

@kartik210

# Kartik Kumar

@kartik210 · Joined January 2026

Grinding the Thoughts

### [Map and Set in JavaScript](https://javascript-kartik.hashnode.dev/map-and-set?utm_source=hashnode&utm_medium=feed)

Map and Set is a JavaScript object used to store collection of data like in arrays but they have some few differences. What Map is Map stores a collection of key value pairs where key can be of any da

2 min read · [javascript-kartik.hashnode.dev](https://javascript-kartik.hashnode.dev/map-and-set?utm_source=hashnode&utm_medium=feed)

[May 7](https://hashnode.com/posts/map-and-set/69fccbd19f93a850a4f75009)

### [Array Flatten in JavaScript](https://javascript-kartik.hashnode.dev/array-flatten?utm_source=hashnode&utm_medium=feed)

What nested arrays are Array inside array is called nested array. Why flattening arrays is useful One of the usecase is that we want all users post in single array to display it. const users = \[ { n

1 min read · [javascript-kartik.hashnode.dev](https://javascript-kartik.hashnode.dev/array-flatten?utm_source=hashnode&utm_medium=feed)

[May 6](https://hashnode.com/posts/array-flatten/69fb86f050ecad453360015b)

### [URL Parameters vs Query Strings in Express.js](https://javascript-kartik.hashnode.dev/url-parameters-vs-query-strings?utm_source=hashnode&utm_medium=feed)

What URL parameters are URL parameters are the segments passed in the url. What query string are Query string is the data passed with the url but it does not affect the segment of the url. It is the p

2 min read · [javascript-kartik.hashnode.dev](https://javascript-kartik.hashnode.dev/url-parameters-vs-query-strings?utm_source=hashnode&utm_medium=feed)

[May 6](https://hashnode.com/posts/url-parameters-vs-query-strings/69fb812b50ecad45335bb98a)

### [The new Keyword in JavaScript](https://javascript-kartik.hashnode.dev/new?utm_source=hashnode&utm_medium=feed)

What is new keyword new keyword is used to create instances from the constructor functions. What the new keyword does new keyword does four things when used with constructor function 1) Create an Empt

1 min read · [javascript-kartik.hashnode.dev](https://javascript-kartik.hashnode.dev/new?utm_source=hashnode&utm_medium=feed)

[Apr 1](https://hashnode.com/posts/new/69cd6bef3085402b9c507b21)

### [Understanding the this Keyword in JavaScript](https://javascript-kartik.hashnode.dev/this?utm_source=hashnode&utm_medium=feed)

This article is inspired by mdn this keyword article and I have created this diagram to understand this keyword in my own understanding. Lets deep dive into this keyword. This will be the final stop t

4 min read · [javascript-kartik.hashnode.dev](https://javascript-kartik.hashnode.dev/this?utm_source=hashnode&utm_medium=feed)

[Mar 31](https://hashnode.com/posts/this/69cc208ce4688e4edd30c85f)