How JavaScript is different from Java

Many novice developers think that Java and JavaScript are related. They think you need to learn Java first, and then Script in addition, and that’s it.) In fact, they are very different languages – they are differently designed and used for different tasks.


Every computer language has data types: strings, numbers, symbols, and so on. But every language handles them differently, this is called typing. In languages like Java it is static: if you type a numeric variable, you first have to type it. The computer looks at the type and knows: this is going to be math.

In JavaScript the typing is dynamic, so you don’t have to set the types. On the one hand there is freedom and rock’n’roll, but on the other hand different anomalies are possible.

But it’s safer this way – the language protects the programmer from his own mistakes. Don’t compare bananas with numbers!


Unlike JavaScript, Java is a compilable language. Before we can run Java code, we have to compile it-that is, translate it into machine language. But then, when we click on the program icon, the code will immediately start executing. You don’t need to compile anything when you run it again.

The scripts are first intercepted by the interpreter, which does approximately the same thing, but in real time. That is, every time the script is run, the JavaScript code is translated into machine code.


The magic of the Java language is in its virtual machine (JVM). The virtual machine allows you to run the code on any device where it is installed. If the machine can be started, the program will be started. This makes it easy to write software in Java for many different devices: servers, computers, smart phones, ATMs and even robots.

JavaScript has a different kind of control over the elements of a page. You can write a useful script and add functions to the site. And if you learn Node.js, you won’t need any other language at all – you can even program a socket.

What is easier to learn

The short answer is JavaScript. To write your first script, no need to spend time installing a virtual machine and understand the types of data. And the tools you will need only a notepad and a browser. Choose it if you are a complete beginner and want to get up to speed quickly.

In the beginning, you’ll sweat in Java, but later you’ll be able to run complex systems. It’s also easy to switch from Java to other languages – Kotlin or C#.