Java vs JavaScript- All You Should Know

Look around and you will find many web developers, but everyone would not tell you the difference between Java and JavaScript. A famous web developer quoted the difference between these two as- “Java is to JavaScript as Ham is to Hamster”. Basically, there are no links between both languages. Both the languages serve completely different roles in web development and programming. Let us move further and look for the differences and similarities between them-

WHAT IS JAVA?

Java is a general-purpose programming language. Applications built in Java are compiled to bytecode with the help of Java Virtual Machine (JVM). In web development, Java is a server-side language which is prominently used in developing mobile applications for Androids. Apart from this, it is present as a front-end language as Java applet but is not used due to security reasons. Java-vs-JavaScript--650x162

WHAT IS JAVASCRIPT?

It is a scripting language which is considered to be one of the three core components of the web that runs in the browser and makes web pages dynamic and interactive. It is employed by a majority of websites. It is rapidly growing as a server-side language along with Node.js.

JAVA VS. JAVASCRIPT: MAJOR SIMILARITIES

Though they are different languages, there are some differences worth considering-
  • Object-Oriented Programming (OOP)
OOP both languages access to techniques like inheritance, encapsulation, and polymorphism. Both languages work on the object and their relationship with other objects.
  • Front-End Development
Both languages are used for front-end development. JS can be embedded directly into HTML, implemented as a framework or library; Java can be used as a Java applet.
  • Back-End Development
These languages are used on the server-side. Java has been used to power back-end technologies like Apache, WebSphere, and etc; whereas JavaScript-powered servers use Node.js for the same purpose. java-vs-javascript

JAVA VS. JAVASCRIPT: MAJOR DIFFERENCES

Despite having some similarities, let us not forget that both the languages were developed to serve completely different purposes. Where Java was designed to develop standalone applications, JavaScript was built specifically to interface with technologies like HTML. Let’s check out the major differences between two-
  • Compiled vs. Interpreted
While Java is considered as compiled programming language, JavaScript is considered as interpreted scripting language. Java is compiled into bytecode as mentioned above, whereas JS can be interpreted directly by a browser.
  • Type checking
Java uses static type checking where variable type is checked at compile-time. While JavaScript uses dynamic type checking where type safety is verified at runtime. It is not required for the programmer to specify the type of any variable they create in the case of JavaScript. The advantage of type checking is that less time is required to execute a code using less memory if static type checking is chosen. The primary advantage of dynamic type checking is programmer productivity—you are free to assign types at your leisure.
  • Concurrency
It refers to the ability handle the execution of several instruction sequences at the same time. Java makes use of multiple threads to perform tasks in parallel, whereas JavaScript handles concurrency on one main thread of execution with an even loop, and a forking system called Node clustering.
  • Class-Based vs Prototype Based
Java follows class based inheritance i.e. top-down, hierarchical, a class-based relationship whereby properties are defined in a class and inherited by an instance of that class. While in JavaScript, inheritance is prototypical- all objects can inherit directly from other objects.

You should consider Java if your project involves-

  • Android Apps
  • Enterprise Software
  • Scientific Computing
  • Big Data Analytics
  • General Purpose Programming of Hardware
  • Server-Side Technologies like Apache, JBoss, Geronimo, GlassFish, etc.

You should consider JavaScript if your project involves-

  • Dynamic single page applications (SPAs)
  • Front-End technologies like jQuery, AngularJS, Backbone.js, Ember.js, ReactJS etc.
  • Server-Side technologies like Node.js, MongoDB, Express.js, etc.
  • Mobile App Development through PhoneGap, React Native, etc.ot
In a nutshell, both languages are meant for different purposes and there is no way you can use these terms interchangeably.