Introduction
To be fair, both languages have a bit of a mixed history. Java is a statically defined object-oriented language developed by Sun Microsystems and released in 1995. Originally developed for television, Java eventually found its way into server-side applications. JavaScript, on the other hand, is a dynamically defined object-oriented programming language developed by a company called Netscape to make web applications more interactive. To compete with Internet Explorer during the browser wars, Netscape asked Sun Microsystems to license the Java protocol. This would have allowed them to run Java applications in Netscape's browser. In return, Sun requested that the JavaScript language (then called Mocha) be renamed JavaScript. But that's where all the similarities between the two languages end. But what is Java? And what is JavaScript?
What is Java?
Java is a statically typed object-based programming language. Its ability to run on a virtual machine (Java Virtual Machine) makes it platform-independent (i.e., it can be run on any device because it can be run in a simulated virtual environment.) What do we mean when we say it is statically typed? A statically typed language is one that is coded with a strict syntax, meaning that when you define a variable, you must specify from the beginning what data type it will be assigned to. Once declared, you cannot change this. This is a significant difference in both languages, as we will see in the case of JavaScript.
What is JavaScript?
On the other hand, JavaScript is a dynamically typed object-oriented programming language that, unlike Java, does not require any setup or installation, as it runs in a computer browser. Dynamic typing means any language with a more flexible syntax. You do not need to specify the type of data assigned to a variable because this data can be changed or reassigned later. JavaScript is designed as a programming language that is relatively simple and lightweight. It is designed to work alongside CSS and HTML to provide more interactivity in the web browser experience.
Key differences
Implementation (how it works):
While both programs output the phrase “hello world,” you can only run JavaScript code through a browser. In contrast, a Java program can be compiled into a virtual environment, allowing it to run on almost any machine independently of any other program. You can run a Java program on your smart refrigerator. However, JavaScript requires an interpreter to run and must be embedded in a browser’s HTML. This is one of the notable differences between the two computer languages.
Complexity:
As you can see from the code snippets, Java is a more powerful and complex language. This is necessary to maintain its ability to run independently of other programs. JavaScript, on the other hand, is designed to be lightweight, but it sacrifices its independence to achieve that. With a much simpler syntax, it can produce results similar to a more complex programming language like Java, but it relies on an interpreter, i.e. the browser, to execute it.
Ease of learning:
Although Java is a more complex language than JavaScript, it is relatively easy to learn. JavaScript is designed to be simple and lightweight as a programming language that relies on the browser to run. This allows the browser to efficiently execute embedded scripts without putting too much strain on the user's internet connection. This helps ensure a consistent browsing experience across geographical regions with varying internet connection speeds. These differences play into their strengths. Both were intentionally designed for these reasons. Java, due to its complexity, can run independently on multiple platforms and hardware. JavaScript, due to its simplicity, can run in lightweight applications such as browsers.
File format:
While it may seem obvious, you don't want to spend hours wondering why your scripts or programs aren't running, only to realize you saved them with the wrong file extension. Java uses the .java file extension, while JavaScript uses the .js file extension.
Support:
Since it is a compiled and interpreted language, most devices with an operating system can run Java programs. JavaScript has varying compatibility. As a programming language, it is designed to be embedded within other types of code, such as HTML and CSS. This makes it more browser-dependent, regardless of the underlying operating system. The good thing is that most browsers support JavaScript.
Java Applications
Industrial and organizational scale development:
Think of all the smart equipment you know, like factory production lines and large farm equipment. Although it rarely crosses our minds, those systems and machines are giant computers. They may not have the typical screens and interfaces we associate with computers, but they do, and computers need to run programs to be useful. Java is well-suited for writing programs for these systems because it can be compiled and run independently, without relying on a browser to execute its code.
Android Development:
Similar to its use in applications and industries, Java is also particularly well-suited for Android app development. There are many examples of JavaScript and browser-based games, even complex ones. However, to get the depth of interactivity we expect from our gaming experience and still have the ability to run consistently across devices with different specifications, you need to use a compiled language like Java.
Back-End Server Calculations:
Java has been very useful in back-end server programming. While you can interact with JavaScript a little, any feature that requires more complexity must be implemented on the server. This means that the browser initiates the request while the application on the server processes and delivers the results to the browser. Server-side programming is essential because it allows developers to provide a consistent experience to users regardless of the computer specifications.
Smart devices and the Internet of Things:
The world is becoming more connected. In the last year or two, we have seen the introduction of many smart and connected devices. These devices require programs to run in order to function and connect to the network. Java's powerful syntax and independence have made it the default choice for running these devices.
Uses of JavaScript
Creating dynamic and interactive web pages:
JavaScript is designed to make web pages more dynamic and interactive. It is designed to work alongside other languages like HTML and CSS to provide a richer and more immersive web experience. Creating and hiding menus, hover effects, zooming capabilities on images, and fancy menus like hamburger-style menus are all achieved using JavaScript.
Applications:
JavaScript's large install base and supportive community have helped push the boundaries of what is possible with this simple-to-syntax language. With JavaScript protocols like React, React Native, and Node.js, it is now possible to build mobile apps and achieve back-end development using JavaScript.
Game development:
Although it is not as widely used for game development as Java, there are a few popular games that you would be surprised to know were developed using JavaScript. Angry Birds and Bejeweled would be two famous examples. Developers are constantly expanding the possibilities of JavaScript-based browser-based games.
Which should we learn? Java or JavaScript?
Now that we have a good understanding of both languages, their differences, strengths, and use cases, the question that may be on your mind is which one of these languages should I study first as a beginner programmer. Well, the answer would be, “it depends.” Are you more inclined to build for the web or build native apps for smartphones and smart devices? And if you have decided that you want to design for the web, do you want to create front-end or focus on increasing the engagement on websites and the web experience through the back-end? Your answers to these questions, through a little self-reflection, should lead you towards the answer to the question. Let’s say you want to design for the web and you are interested in front-end web development. In that case, you should learn JavaScript first. Although JavaScript is increasingly used for back-end applications, if you are only interested in back-end development, there are more robust programs like Python that are great at the back-end and easy to learn. However, if you are interested in developing mobile apps and the connected future – smart devices and the Internet of Things – Java will be your language. In terms of ease, if you haven’t decided on a specific path and just want to get your feet wet with coding, most people start with web development, learning HTML and CSS, and understanding the structure of the web experience. JavaScript will be the language to learn, as it pairs with CSS and HTML to deliver the web experience we now call a browser.
