Is closure a function? What is a nested function? What is a function scope? What is lexical environment and how does it work?
In this article, we’re going to answer all these questions and more – we are going to learn what functions and closures in JavaScript are, and most of all what is the main difference between functions and closures.

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Functions and procedures are probably some of the most common words in programming terminology you will hear, and occasionally people even use these terms interchangeably, which is, you guessed it, wrong. Therefore, the question we will explore in this article is, what is a function, a procedure, the difference in programming language terminology between function and procedure, and most of all what is the difference in terms of function vs. procedure functionality and their use. So, let’s dig it.

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We already wrote about querySelector(s) in the article where we compared querySelector to getElementById. In that article, we covered the basics, but there is so much more to querySelectors in JavaScript. They are a superpowerful tool, so we really want to introduce you to some basic and a bit more complex QuerySelector rules in JavaScript.

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In this article, we will take a look at JavaScript render-blocking. We recognize 3 types of render-blocking, as stated in the title of this blog post, but first, let’s take a look at what (browser) rendering is.

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Which is better – getElementById or querySelector? Well, better is a very subjective answer. Both getElementById and querySelector are an element-grabbing method from the JavaScript Document Object Model (DOM), so with each method, you can pick up whatever element you want to manipulate with, of course depending on the circumstances. The advantage at least is that you don’t have to choose which one you’ll use – both, GetElementById and querySelector method have their own use cases and you can choose methods interchangeably. However, the question remains – why use one over the other? So, let’s dive in.

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In this article, you are going to learn the difference between arrow functions vs traditional (regular) functions in JavaScript through a few examples – we are going to browse through differences and similarities and learn when to use each.
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In JavaScript, null and undefined may look the same, but they are not. In this article, you will learn the differences and similarities between null and undefined in JavaScript, and when you should use each.
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In this article, you are going to learn more about JavaScript functions and methods. In short – a function can live on its own, it does not need an object, but a method is a function connected with an object property, but let’s take a look and see what are the similarities and differences between functions vs. methods in JavaScript.
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In this article, you’re going to learn the difference between JSON and JavaScript object.
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Should I use single (‘) or double (“) quotes when working in JavaScript? That’s the question now.

'abc' === "abc" // true

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