JavaScript may be a programming language (also referred to as scripting). All developers square measure at home with JavaScript to a point. From easy animations on web content to advanced interactions, we’ve all found ourselves victimization it a minimum of once.

JavaScript may be a programming language originally born online. Brendan Eich, the creator of JavaScript, found himself operating web browsers in 1995. The project manager assigned Brendan an on-the-face it not possible task: to form a programming language that worked within the web browser Navigator browser.


Brendan Eich formed JavaScript (originally named Mocha), which was developed in exactly ten days. The results of those ten days of development? An odd language, decorated with things that square measure themselves strange. Since that point, JavaScript has become the universal language of the online, though it’s ne’er enjoyed a stellar name.

History of JavaScript

JavaScript is omnipresent, and it’s the most popular programming language for the eighth year in a row, with 67.8 percent of developers using it in 2019. Its rise to become the world’s most popular programming language parallels the rise of the internet.

Created out of necessity, it is used to build 95.2% (1.52 billion) of websites today, including some of the world’s largest, like Facebook and YouTube. Without it, we would not have popular and useful web apps such as Google Maps and eBay. 

So, without further ado, let’s take a look at what JavaScript is,  how and why it was created, and what’s next for the language.

What is JavaScript used for?

As mentioned, JavaScript is a programming language for creating dynamic objects on pages or websites. With this language, it is possible to alter and modify every single element on the page to our liking and without limits.

Some of the main uses of JavaScript are as follows:

  • Adding custom HTML elements
  • Adding and editing items even after the page has loaded
  • CSS modification (element style changes)
  • Creating dynamic elements
  • Creation and compilation of forms
  • Sending and receiving data
  • Saving and loading files
  • File generation
  • Notices
  • Effects
  • Animations
  • Programming in general and much more

It might be difficult to understand at first glance, but JavaScript is a powerful programming language with which it is really possible to act on any single object very easily or create whatever you have in mind. The only limit is your own knowledge.

Features of JavaScript

The characteristics of JavaScript are described in detail in the following article. Brendan Eich created JavaScript in 1995 for scripting on web pages, allowing logical operations to be performed at the client edge. JavaScript is mostly used as a client-side scripting language. This object-centered script language, which was developed in Netscape, is most widely used for developing web pages. It gives the user more control over the browser and allows for the creation of new script functionalities. This scripting language supports case-sensitive input as well as browser and operating system detection. Validation in client edge technology frequently employs JavaScript.

The following are more characteristics of JavaScript:

  1. Object-Centered Script Language
  2. Client edge Technology
  3. Validation of User’s Input
  4. Else and If Statement
  5. Interpreter Centered
  6. Ability to perform In Built Function
  7. Case Sensitive format
  8. Light Weight and delicate
  9. Statements Looping
  10. Handling Events

Advantages of JavaScript

Firstly, we will discuss the benefits or advantages of using JavaScript –

1. Speed

Because JavaScript is an ‘interpreted’ language, it takes less time to compile than other programming languages like Java. JavaScript is a client-side script that speeds up program execution by eliminating the time spent connecting to the server.

2. Simplicity

JavaScript is simple to learn and understand. The framework is straightforward for both consumers and developers. It’s also simple to implement, saving web developers a lot of time and money when creating dynamic content.

3. Popularity

Since all modern browsers support JavaScript, it is seen almost everywhere. All the famous companies use JavaScript as a tool including Google, Amazon, PayPal, etc.

4. Interoperability

Because JavaScript works well with other programming languages, many developers use it to create a variety of applications. We can put it on any website or in a script written in another computer language.

5. Server Load

Because JavaScript works on the client-side, data validation can be done in the browser rather than on the server. The entire website does not need to be reloaded if there is a discrepancy. Only the selected portion of the page is updated by the browser.

6. Rich Interfaces

Developers can use JavaScript to create appealing websites using a variety of interfaces. Websites with drag-and-drop components or sliders may have a richer interface. As a result, the webpage’s user interactivity improves.

7. Extended Functionality

Third-party add-ons, such as Greasemonkey (a Mozilla Firefox extension), allow developers to save time and money by inserting prefabricated code snippets into their code. These add-ons make it considerably easier for developers to create JavaScript applications than with other programming languages.

8. Versatility

JavaScript can now be used for both front-end and back-end development. NodeJS is used for back-end development, whereas AngularJS, ReactJS, and other libraries are used for front-end development.

9. Less Overhead

JavaScript improves the performance of websites and web applications by reducing the code length. The codes contain less overhead with the use of various built-in functions for loops, DOM access, etc.

Disadvantages of JavaScript

Now after discussing the advantages of using JavaScript, its time to have a look at some disadvantages of using JavaScript which we have briefly discussed below –

1. Client-side Security

Because the JavaScript code is visible to the user, it could be used maliciously by others. Using the source code without authentication is one of these methods. Furthermore, it is relatively simple to insert code into the site that undermines the security of data transmitted over the internet.

2. Browser Support

In different browsers, JavaScript is interpreted differently. As a result, the code must be tested on a variety of systems before being released. Some new functions aren’t supported by earlier browsers, so we’ll need to verify those as well.

3. Lack of Debugging Facility

Though some HTML editors support debugging, it is not as efficient as other editors like C/C++ editors. Also, as the browser doesn’t show any error, it is difficult for the developer to detect the problem.

4. Single Inheritance

JavaScript only supports single inheritance and not multiple inheritances. Some programs may require this object-oriented language characteristic.

5. Sluggish Bitwise Function

A number in JavaScript is stored as a 64-bit floating-point number, and operators work with 32-bit bitwise operands. As a result, JavaScript converts the number to 32-bit signed integers, performs operations on them, and then converts them back to JavaScript numbers. When converting a number to an integer, this continuous conversion takes longer. This lengthens the time it takes to run the script and slows it down.

6. Rendering Stopped

A single code error can stop the rendering of the entire JavaScript code on the website. To the user, it looks as if JavaScript was not present. However, the browsers are extremely tolerant of these errors.

Is JavaScript easy to learn?

This is one question that always comes up when it’s time to learn a new programming language. Or it is for me, at least.

To be clear, it’s unlikely to find a programming language on this planet that’s explicitly easy to learn. It’s like learning anything else that’s new to you. You’ll need to work hard to see results.

But the truth is:

Some programming languages are easier to learn than others. This has a lot to do with how you use them and how they read.

For example, Python reads a lot like English, which makes it a beginner-friendly programming language.

Recommended: How to Find the Easiest Programming Language for Beginners?

Out of the three front-end development languages (HTML, CSS and JavaScript), it is, of course, the most difficult one to learn. But that’s just because HTML and CSS are markup languages rather than programming languages.

I’m not saying HTML or CSS is easy to learn, but they have a different sort of complexity to them.

How to learn JavaScript fast

Although you’ll need heaps of time to learn JavaScript and fully understand how the language works, you can start building meaningful projects early on.

And that’s what it all boils down to applying what you learn to build programs on your own.

So, when you start learning JavaScript (or any other programming language), make sure you don’t just watch video lectures all day long.

While you’re going through your lectures, take notes. Then, after each lecture, try to use what you just learned to build a small program on your own.

If it feels difficult, look for help in your notes first. They should be good enough to remind you what to do. And if not, take better notes during your next lecture!

But why should you take notes? Can’t you just go back and watch your video lecture again?

You can, yes. But that kind of “monkey see, monkey does” approach won’t help you learn how to code by yourself. May sound harsh, but that’s the reality.

When I started learning to code, I was watching video lectures and repeated whatever exercises they showed. I felt like I was doing progress, but I soon noticed that when I didn’t have those lectures at hand, I couldn’t build anything by myself.

Therefore, don’t underestimate the importance of

  1. Taking notes and
  2. Building small projects of your own

Recommended Javascript Projects

Practical tips to learn JavaScript for beginners

Furthermore, you can use a bunch of helpful learning strategies to speed up your learning.

Whether you’re learning JavaScript or another language, try these tips:

  1. Focus on one language at a time:
    Don’t get distracted by another programming language you find intriguing. Learn your current one well before the next.
  2. Finish every coding course you start:
    When you’ve started one, make sure you finish your online coding course before starting the next one. The lectures build on top of each other, so you want to make it to the last one. That’s where you’ll learn the “good stuff”, i.e. the more advanced lessons.
  3. Keep your long-term goal in mind:
    For example, if you want to learn JavaScript to become a freelancer, keep your eyes on the prize. When you know what you want to do with coding in the future, you won’t run out of motivation along the way.

Since JavaScript uses variables, functions, and loops, it’s easier to learn JavaScript if you already know another programming language.

For example, I learned Python before I started learning JavaScript. With a good understanding of how programming languages work in general, I managed to learn JavaScript much faster than Python.

To speed up your learning, even more, my #1 recommendation is to learn some Computer Science basics before coding.

Integrate JavaScript into web pages

1. In-line code

In HTML pages each element is defined by means of special tags with specific functions. The integration of JS codes within HTML pages is possible simply by defining one of these tags in any desired position.

In fact, JavaScript lives inside web pages through the <script>… </script> tags.

These tags can be multiple on the same page, we can also say unlimited.

Furthermore, unlike many other HTML elements, <script> can be inserted in both <body> and <head> without particular distinction. The choice falls on the basis of needs, many scripts in fact need to be executed before rendering or loading the page to work.

In the case of secondary or manual scripts, it is possible (and recommended) to define them in the page footer, in the lowest position, in order to make the page load faster.

2. External code

Another method for integrating JavaScript code into an HTML page is through external files in .js format Much like CSS, you can call external JavaScript resources on a page like this:

<script type=”text/JavaScript” src=”codici.js”></script>

The URL or path of the file in .js format must be entered in the “src “attribute. The position of the HTML tag follows the same rules of in-line writing as in the previous section.

NB In the <script> tag it is possible to add an instruction on the format defined by the “type” attribute (type =” text / JavaScript “). In the latest versions of JS, it is mandatory to indicate this instruction.


Below is an example of opening the JavaScript code in an HTML page, devoid of actual useful code.

<! DOCTYPE html>



      <script type=”text/javascript”>








      <script type=”text/javascript” src=”codici.js”></script>



3. JavaScript rules

The JavaScript code to be executed correctly by browsers must respect certain rules; otherwise it will be easy to run into unpleasant errors.

These rules are easy to remember and we can summarize them in these points:

  • Each line of code must end with a semicolon (;).
  • JS is case sensitive, that is, it distinguishes between lowercase and uppercase letters (“Name” is different from “name”.
  • The custom name of variables, objects and functions cannot start with a number or symbol.
  • The separation of words that make up a custom value/name can be defined with the symbol “_” (underscore).
  • Furthermore, custom names cannot have spaces between the words that compose them
  • It is recommended to use names like my Variable or my_function for example.
  • To define text strings or values, they must be enclosed in single (‘) or double (“) quotes, otherwise, they will not be executed and will return errors.
  • You cannot give prohibited names to variables or functions. For forbidden we mean those pre-imposed names present in the language that already have established functions such as function, while, for, in, do, return, this, etc …

Keep these concepts in mind but don’t give them too much weight, you will see everything in detail in the following articles.

JavaScript is a typed language but without too many restrictions or constraints, that is, to be executed it does not need an ordered and specific structure, but is able to interpret scripts even with any errors and shortcomings, compensating the absent values ​​with those it deems most appropriate (example ‘absence of a semicolon or repetition of variables).

JavaScript is a language that executes “cascading” instructions, i.e. from first to last in order of writing on the page. Any statement executed after, if required, can overwrite a previous one.

Therefore pay close attention to writing the code and try to be as orderly as possible following the hierarchy of elements.

This was the introduction to JavaScript for the first article of our course, which as mentioned will be for beginners. Also in the next ones, we will try to give detailed explanations without superfluous information because JS like many other programming languages ​​are based a lot on constant practice.

If you want to learn more, you can take a look at the “HTML & JS functions ” section of our site, you will find many useful tutorials to start programming with JS in a simple and intuitive way.

Javascript Developer Salary

The national average salary for a Javascript Developer is $90,864 in the United States. Filter by location to see Javascript Developer salaries in your area. Salary estimates are based on 163 salaries submitted anonymously to Glassdoor by Javascript Developer employees.

If you enjoyed this post on what is JavaScript, drop me a line in the comments below!

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I’ll see you in the next post! Happy coding!

One Comment

  1. Anil Kumar Sah

    Thank for this… Really Useful

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