4 min read

If you are new to JavaScript, you may find it a little confusing depending on what computer language you were using before. Although JavaScript is my favorite language to use today, I cannot say that it was always this way. There were some things I truly disliked and was genuinely confused with in JavaScript. At this point I have come to accept these things. Today we will discuss the five hurdles you may come across in the JavaScript programing language.

Global variables

No matter what programming language you are using, it is never a good idea to have variables, functions, or objects as part of your global scope. It is good practice to limit the amount of global variables as much as possible.

As programs get larger, there is a greater chance of naming collisions and giving access to code that does not necessarily need it by making it global. When implementing things, you want a variable to have a large enough scope as you need it to be.

In JavaScript, you can access some global variables and objects through window. You can add things to this if you would like, but you should not do this.

Use of Bitwise Operators

As you probably know, JavaScript is a high level language that does not communicate with the hardware much. There are these things called Bitwise Operators that allow you to compare the bits of two variables. For instance x & y does an AND operation on x and y. The problem with this is, in JavaScript there is no such thing as integers, only double precision floating point numbers. So in order to do the bitwise operation, it must convert x and y to integers, compare the bits, and then convert them back to floating point numbers.

This is much slower to perform and really should not be done, but then again it is somehow allowed.

Coding style variations

From seeing many different open source repositories, there does not seem to be one coding style standard that everyone adheres too. Some people love semicolons, others hate them. Some people adore ES6, other people despise it.

Personally, I am fan of using standard for coding style, and I use ES5. That is soley my opinion though. When comparing code with other people who have completely different styles, it can be difficult to use their code or write something similar.

It would be nice to have a more generally accepted style that is used by all JavaScript developers. It would make us overall more productive.


Coming from a class-based language, I found the topic of prototypical inheritance difficult to understand and use. In prototypical inheritance all objects inherit from Object.prototype. That means that if you try to refer to a property of an object that you have not defined for yourself, but it exists as part of Object.prototype, then it will execute using that property or function.

There is a chain of objects where each object inherits all of the properties from its parent and all of that parents’ parents. Meaning, your object might have access to plenty of functions it does not need. Luckily, you can override any of the parent functions by establishing a function for this object.

A large amount of falsy values

Here is a table of falsy values that are used in JavaScript:

False Value













All of these values represent a different falsy value, but they are not interchangeable. They only work for their type in JavaScript. As a beginner, trying to figure out how to check for errors at certain points in your code can be tricky.

Not to harp on the problem with global variables again, but undefined and NaN are both variables that are part of global scope. This means that you can actually edit the values of them. This should perhaps be illegal, because this one change can affect your entire product or system.


As mentioned in the beginning, this post is simply an opinion. I am coming from a background in C/ C++ and then to JavaScript. These were the top 5 problems I had with JavaScript that made me really scratch my head. You might have a completely different opinion reading this from your different technical background. I hope you share your opinion! If you enjoyed this post, tweet and tell me your least favorite part of using JavaScript, or if you have no such problems, then please share your favorite JavaScript feature!

About the author

Antonio Cucciniello is a Software Engineer with a background in C, C++ and JavaScript (Node.Js) from New Jersey.   His most recent project called Edit Docs is an Amazon Echo skill that allows users to edit Google Drive files using your voice. He loves building cool things with software, reading books on self-help and improvement, finance, and entrepreneurship. Follow him on twitter @antocucciniello, and follow him on GitHub here: https://github.com/acucciniello

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