Java vs. JavaScript. Which One Is The Best Choice for Learning in 2023

It’s like Java and JavaScript, the programming languages are just bound to be pitted against each other forever. It starts with the name. JavaScript was doomed to be eternally confused as some extension to Java, and indeed it is confused with Java, a lot. Even to this day, in 2023. Of course, we at CodeGym venture to hope that our esteemed audience is proficient enough to be well aware that Java and JavaScript are two different programming languages. Although this doesn’t put Java and JavaScript out of the ring just yet. With more than 7 mln and 12 mln developers worldwide respectively, these two languages compete with each other (and with Python as the third contender) for the title of the most used and in-demand programming language in the world. So it is perfectly natural for beginners in programming to compare Java and JavaScript when trying to decide which language to learn as their first. And that is not the decision to take lightly as the choice of the language would easily shape all your future career in software development, if you will have one or at least planning to. So understanding the differences between these languages, as well as similarities, is quite important. But first, a quick introduction of both languages.

Java

Java has been the top choice in the enterprise and mobile sectors for a while now and will continue to do so in the foreseeable future. Being one of the most versatile programming languages in the world, Java these days is used almost everywhere in terms of platforms, technologies, and economy sectors. It is currently the most popular backend programming language in mobile development (Android, primarily), as well as very common in cloud-based solutions and in a number of other hot and trending tech niches such as IoT and Big Data. Today the total number of Java developers globally is over 7 mln (based on different estimates, there are 6.8-8 mln Java coders in the world), which puts it on the third spot behind only JavaScript and Python. As for the demand for Java developers, it stays at a very high-level year after year. According to a recent report by analytical company Burning Glass, Java Developer is one of the most common tech occupations in the U.S. Java is also one of the most requested tech skills overall. Interestingly, one study has found that Java developers are the least likely to leave their profession among all professionals in general, not just in the tech sector. Their career-switch rate is less than 8%, while for the software developer profession in general it’s 27%, and for database administrators, for example, it’s 35%. Even when offered a higher-level managerial position, the majority of Java coders just don’t want to give it up. This may be the best proof of Java programming being the right profession choice for the majority of coders.

JavaScript

JavaScript is the king of modern-day frontend development. Initially released in early 1996 during the “first browser war" between Microsoft with its Internet Explorer and Netscape's Navigator, these days JavaScript is the most obvious choice for designing interactive frontend applications thanks to a number of strengths. JavaScript is a multi-paradigm, high-level, and dynamic programming language. It became especially popular in the late 2000s when NodeJS, which is a JavaScript-based run-time environment, was released. Node.js allows developers to use the same language for server-side and client-side scripts, making it possible to produce dynamic web page content on the server-side before it is sent to the user's web browser. AngularJS, which is a JavaScript-based web development framework, is another important technology that makes JavaScript so popular and common in web development these days. Today JavaScript is the most popular programming language in the world based on the total number of coders — over 12 mln.

Java vs. JavaScript: a comparison of the common ground

As a perceptive reader should guess, Java and JavaScript have more differences than similarities. Although they do have some things in common. Here are the main similarities of these two programming languages.

• Object-Oriented Programming (OOP).

Both Java and JavaScript follow the principles of object-oriented programming, requiring developers to write the code objects and their relationship in the context of each other. It means that both languages support major OOP concepts, such as abstraction, encapsulation, classes, inheritance, polymorphism, etc.

• Frameworks and libraries.

And both Java and JS have tremendously huge developer communities and corporate support, which results in countless libraries and frameworks for these languages available. That allows developers to use them for various purposes and scenarios, simplifying and speeding up the development process.

• Applications in front-end development.

Another major similarity is that both Java and JavaScript are used in front-end development, even though JS is considered to be a front-end language in a much bigger way. If Java is most used in front-end in the form of applets, JavaScript code runs directly in modern web browsers being implemented into HTML and allowing browsers to perform various functions.

• Applications in backend development.

But they both can power the backend as well. Java primarily, since it was always considered mostly backend language used on the server-side to power the server-side of apps, websites, and various enterprise solutions. More than 90% of all enterprises use Java as their main backend language. Thanks to the existence of new technologies such as Node.js, which is a JS runtime environment, JavaScript can also be used to run the server-side.

What is the difference between Java and JavaScript

But these two have a lot more contradictions in them rather than similarities. Let’s look at the most notable differences between Java and JavaScript.

• Applications and usage.

The major difference is in the way these two languages are used in the tech industry and what roles they play. As you may know, Java has a whole range of applications in various segments, including enterprise solutions, Android development, embedded computers, Big data, and many others. JavaScript, on the other hand, is the language with the main purpose being to make websites and pages more interactive for the user. Even though developing all kinds of interactive elements for websites is a very common and demanded work, you could definitely say that Java development is a lot more comprehensive and all-inclusive.

• Complexity and learning curve.

But being so comprehensive and omnipresent comes with a price: Java can certainly be considered as the language that is considerably more difficult to learn compared to JavaScript. Even the Java Core part includes multiple concepts and features to learn, such as data abstraction, encapsulation, inheritance, polymorphism, and so on. And knowing only them would not be enough to start developing actual programs. JavaScript, on the other hand, is considered to be the easiest of all to learn among modern programming languages. In fact, it is not even a programming language in a strict sense. JavaScript is primarily a scripting language because it embeds scripts into the web browser, which has a built-in JavaScript engine that executes JS code. The main concepts and fundamental principles of JavaScript can be learnt in a few days.

• Execution.

Execution of the code is another major difference. As we already mentioned, JavaScript is an interpreted scripting language, so its code is interpreted directly by web browsers. Java, on the other hand, is a compiling language, so its code is compiled and run on Java Virtual Machine.

• Standardization and documentation.

One of the reasons Java is so overwhelmingly popular in enterprise development is the fact that it can be called one of the best documented and standardized programming languages. Clear and consistent documentation and the existence of nourished coding standards make Java very attractive for businesses as they need reliable solutions that can be easily maintained for a long period of time, often by different developers. In JavaScript’s case, the JS ecosystem is a lot more chaotic and ever-expanding, with some programming paradigms and approaches often mixed together. JS frameworks, which are built on top of JS to extend the functionality of this simple language, typically lack standardization and properly maintained documentation. This makes JavaScript in some sense more complex and poorly predictable when used for the creation of modern complex apps and program solutions.

Java vs JavaScript: is there room for rivalry?

But in spite of all the differences and the fact that beginners often put them against one another when choosing which language to learn, in modern-day software development, Java and JavaScript are not really in opposition to each other. In fact, these two can be great when working together. With Java mostly used for backend development and JavaScript being predominantly utilized in front-end, very often these languages can be combined, powering various parts of a single project. So it’s no wonder many professional Java developers today are looking to learn JavaScript as their second language, while JS coders are looking to add Java to the list of their skills. But which one is better to learn first?

Which one to choose? Expert opinions

Strictly speaking, there is no right answer when it comes to choosing which language, Java or JavaScript, to learn, as evidently, they serve very different purposes. And let’s face it, we at CodeGym, one of the most popular and successful online Java courses, might be just a tiny bit biased here. So let us conclude with a number of expert options on the comparison of JavaScript vs Java from software developers with decades of work in this field. “In my experience, people who learn JavaScript as a very first programming language end up with a distorted view, and it takes extra time and effort to undo some of the damage when they move to a different programming language. JavaScript is a very poorly designed, inconsistent language, and learning it first can forge misconceptions and bad habits, especially if the person teaching it thinks that JavaScript is perfectly fine. Now, if you’re going to do web development, you’ll likely need to learn JavaScript anyway. It’s currently a necessary evil in that space. All programming languages have their place, and JavaScript has its place in web development,” said Ken Gregg, an experienced software developer with decades of coding experience. “I learned Java before I learned JavaScript. While they share a similar name, they are very different in design and execution. Java is multi-threaded, JavaScript is single-threaded with non-blocking I/O. One of the most noticeable differences between the languages is their scope of the declaration. Both have very different rules for how variables, functions, objects, methods, .etc behave in a given region. This can make switching from one to the other slightly challenging for a new developer. All that being said: I think it is worth learning the fundamentals in Java first,” commented Ethan Haynes, Software Engineer at Verizon Cloud Platform. If you are a new programmer I would strongly advise Java over JavaScript. Why? Because I believe that it is important for a programmer to have good fundamentals in a compiled language like Java. JavaScript is an interpreted language, the abstraction level is higher than in Java. If you learn Java first and JavaScript a lot of the time you will be like: “Oh, I see why they did that!”. That’s because you know what is happening “under the hood”. On the other hand, if you have experience with languages like C# or C++, I would advise you to learn JavaScript because it is a scripting and primarily a functional language. Learning programming languages which differ in many ways from each other will help you expand the way you think about problem-solving and programming languages,” recommends Denis Ibrahimi. So guys, what do you think? Which language has a more prominent future, or the rivalry is pointless and you should pick them both?