Welcome reader! In this technology guide, I will clearly break down the key similarities and differences between Java and JavaScript. By the end, you‘ll understand the history and technical capabilities of each language so you can decide which one better fits your programming needs.
Java and JavaScript – two of the most popular programming languages in the world. But beyond having "Java" in their names, they actually differ greatly in their capabilities, typical usage, and histories.
My goal here is to distinguish these languages by comparing critical aspects like execution models, typing, platforms, and more. You‘ll also learn about the current landscape and where JavaScript and Java excel today. So let‘s dive in!
Brief Backgrounds
Java traces its roots back to 1991 when James Gosling first began developing the language at Sun Microsystems. The initial goal was more consumer focused – to create interactive television programming that could work across various devices.
After several early iterations, the first official version of Java appeared in 1995. The "write once, run anywhere" (WORA) promise proved popular, especially for delivering applets running right in web browsers.
In contrast, JavaScript‘s history begins in 1995 when Brendan Eich created the language in just 10 days while at Netscape. Originally called LiveScript, it was renamed to align with more popular Java.
But unlike Java, JavaScript was solely designed for improving front-end, client-side scripting and interactivity in websites accessed through Netscape‘s browser.
So in summary:
| Language | Year Released | Initial Purpose |
| Java | 1995 | Interactive TV & cross-platform applets |
| JavaScript | 1995 | Client-side browser scripting |
Key Technical Differences
Despite some superficial similarities in their C-style syntax, Java and JavaScript differ greatly under the hood. Let‘s break it down:
Compiled vs Interpreted
Java is a compiled language, meaning the code you write needs to be converted into bytecode before execution. The Java Virtual Machine (JVM) then interprets this bytecode.
JavaScript is interpreted, so your code gets directly evaluated and executed by the JavaScript engine built into web browsers. No compilation step is required.
Implication? JavaScript tends to have faster execution times.
Static vs Dynamic Typing
Java uses strict static typing, requiring every variable to have a defined type like integer or string. This allows earlier detection of errors but less flexibility.
Conversely, JavaScript uses loose dynamic typing so variables can change types on the fly without type definitions. More flexible but also more prone to bugs.
Platform Dependence
A major goal for Java was WORA – "write once, run anywhere." Java achieves this cross-platform magic through the JVM, which abstracts away environment differences.
Meanwhile JavaScript runs within web browsers. While browser testing is still needed, modern JavaScript works quite smoothly across different operating systems.
Object-oriented Programming
Both Java and JavaScript support OOP, but important differences exist:
- Java uses class-based inheritance, while JavaScript uses prototype-based inheritance.
- Polymorphism also works differently, with Java relying on static typing for ad hoc polymorphism.
I won‘t dive deeper here, but just know OOP works quite differently under the hood!
Hopefully this breakdown gives you a sense of how much Java and JavaScript diverge technically. Now let‘s look at where they currently stand in the programming world today.
Current Landscapes
While no longer used in web browsers, Java remains extremely popular especially for large enterprise applications. The promise of "write once, run anywhere" has stood the test of time even as the technology world has greatly changed since the 1990s!
Oracle now stewards Java advancement and has committed to supporting Java 8 with security updates until at least 2030. Nearly 75% of full-time developers use Java regularly according to industry surveys. It also ranks consistently among the top 2 or 3 languages in terms of overall popularity.
As for JavaScript, its trajectory has been stellar – used by an incredible 97% of all websites thanks to universal browser support. Modern JavaScript now powers entire web frameworks like React, Angular and Vue through advanced capabilities like asynchronous callbacks.
JavaScript also ranks #1 on GitHub with over 3 million open source projects written using the language as of 2022.
So in summary:
| Language | Current Status |
| Java | – No longer supported natively in web browsers – Still very popular for enterprise software – Stewarded by Oracle, Java 8 supported until at least 2030 |
| JavaScript | – Used by ~97% of all websites – Powers popular web frameworks like React – #1 language on GitHub (3M+ projects) |
As you can see, both maintain healthy trajectories even as their roles have specialized over the years.
When Should I Use Each Language?
Based on the backgrounds and technical capabilities covered earlier, Java and JavaScript now tend to excel in different spheres.
Use Java for:
- Building complex back-end systems to power websites and applications
- Enterprise software that needs stability, scalability and cross-platform support
- Developing Android applications
- Any area where static typing provides better certainty
Use JavaScript for:
- Front-end web development – client-side scripting and UI logic
- Adding interactivity or visualizations to basic websites
- Building single page applications with frameworks like React or Vue
- Simple personal or commercial projects where rapid prototyping helps
- Any task where the code might need to run on emerging web platforms
Of course skilled developers can create full stack solutions using both languages. But recognize their sweet spots based on technical tradeoffs and historical strength areas.
Answering Common Java vs JavaScript Questions
Let‘s wrap up by answers some frequent reader questions:
Is Java dying compared to languages like JavaScript?
No way! As covered earlier, Java continues its popularity especially on the enterprise back-end and server-side. The community and support for Java also remains incredibly strong after over 25 years.
Which language has faster execution speeds?
JavaScript will generally execute application logic faster due to being an interpreted language. But Java code can utilize multi-threading and JVM optimization to greatly improve performance.
Should I learn Java or JavaScript first?
Neither! The fundamentals you learn in one will help pick up the other faster. But you can start with either language based on what kind of programming appeals more. Front-end web? Go JavaScript. Building secure enterprise apps? Start with Java.
Can I use Java for web development?
You can absolutely use Java to build server-side logic and systems that power websites built with HTML, CSS and JavaScript. Java enjoys great tooling for API services and other back-end development. Just don‘t plan to use it for UI scripting within the browser.
And there you have it! I hope this article shed light on the key similarities, differences, and use cases for Java vs JavaScript. Both languages continue to thrive, just in slightly different niches. Let me know if you have any other questions in the comments below!
