• Aida Xie

Differences Between Java and JavaScript

Developers and internet users alike have long been confused between Java and JavaScript. In truth, JavaScript has nothing to do with Java; one common thing between them is the word Java, much like in Car and Carpet or Ham and Hamster. Many people still think that JavaScript is part of the Java platform, which is not true. They are two distinct programming languages, each is useful in its way, and each has strengths over the other. One is not necessarily better than the other and programmers use both Java and JavaScript for a variety of different tasks.

Around the early 1990s, in the initial days of the Internet, Internet Explorer and Netscape Navigator were the two most popular web browsers. In just ten days, a programming language that could instruct the computer on how to interact with the user upon receiving user input was created by a developer named Brendan Eich. They called this language "LiveScript" and integrated it directly into Navigator. However, there was another programming language, Java, which was fast gaining recognition at around the same time, Netscape took the opportunity and renamed their language JavaScript.

Java is a programming language currently owned by Oracle, developed by Sun Microsystems, and first invented by James Gosling. It took a bit longer than ten days to develop. It took almost four years. In 1991, a group of Sun Microsystems engineers worked relentlessly to create Java. It was first released in 1995 and has launched multiple new versions since. Our world today is saturated with Java-run applications, and we are thankful for that as they massively help make our lives easier.

Java vs JavaScript

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Several years ago, it would be rather straightforward to summarize the difference between Java and JavaScript. Java is a general-purpose language, while JavaScript programming languages are uniquely for websites, to create animated and interactive elements. The situation is very much dissimilar today as both Java and JavaScript have developed and matured swiftly in the past few years. Let us look at just a few of the differences now.

Execution Environment

First difference and a key one, between Java and JavaScript, is the way of execution. Java code is normally written in an Integrated Development Environment (IDE), compiled into class files containing byte code and run by a Java Virtual Machine but unreadable to humans. On the other hand, JavaScript is usually executed by a JavaScript engine using the same syntax that it was written in, which means they are readable in theory. In reality, JavaScript files sent online are typically compressed to barely legible format. The readability is an important distinction as making changes in a Java IDE can be complex and require specialized software for compiling and deploying the changes. JavaScript, however, can be edited with a simple text editor.

Programming or Scripting

Java is an Object Oriented Programming language, and though JavaScript also supports class and object, it is more like an object-oriented scripting language. It is much easier to structure the code of large enterprise application in Java than JavaScript. Java creates applications run in a browser or virtual machine requiring code compilation while JavaScript runs on a browser alone without creating any standalone applications. Java provides packages to group related class together as well as much better deployment control.


Java is available almost everywhere, and it is an independent programming language which can run on different operating systems. Java uses block-based scoping where variable goes out of scope once control comes out of a block. JavaScript uses function-based scoping; a variable accessible in the function they are declared. If you have a global variable and local variable with the same name, local will take precedence in JavaScript.