What is Java Coding? | Computer Science for Kids 12+

Whether you’re a curious parent or a new coder, you’ve likely heard of the coding language Java before.

Java is very commonly taught in high school, in introductory coding classes such as AP Computer Science. It’s often the first programming language many coders learn!

But despite its popularity, many young students and families still wonder what Java actually is, and who it’s for.

In this article, we’ll explain just that — continue reading to learn more about what Java is, where it’s used, and why it’s one of the most popular programming languages in the world.

The History of Java


Let’s first learn more about how Java came to be.

Java is a multi-platform programming language created in 1995 by James Gosling at Sun Microsystems (now Oracle). Before its current name, the coding language was actually first named “OAK,” after an oak tree that stood outside of James Gosling’s office.

Fun fact: After running into trademark issues with the name “OAK,” Gosling’s team needed to brainstorm some alternatives. During a coffee break, they later settled on “Java” — a unique name inspired by the Java espresso bean! Notice that the Java logo below resembles a cup of coffee.


Since Sun Microsystem’s first version of Java in 1995, the language has evolved over the course of its existence.

Java was actually first originally designed for interactive television! While it was too advanced to be used with the digital cable of the time, it was well-suited to internet programming, and was named one of the Ten Best Products of 1995 by Time magazine.

The Java coding language logo.

The logo for the Java coding language.

Since its first release, many additional features and libraries (a collection of pre-written resources for a given coding language) have been added to Java. As the internet became increasingly popular, more and more people began to contribute and grow Java’s collection of libraries and classes.

This growth is largely thanks to Java being an open-source language — meaning that anyone can publicly contribute to the development of it.

Open-Source Development

The open-source Java community and strong ecosystem of worldwide developers are largely responsible for helping the language evolve to where it is today.

The abundance of Java APIs and other tools built by the large developer community make it easy to write code to accomplish complicated tasks, since a lot of the basic backend code is packaged into APIs (platforms that allow different software applications to communicate) that anyone can use.

open source community for Java

Java has evolved greatly thanks to open-source community contributions.

For example, Java Applets are small applications that are used to provide interactive features to web applications, and can be run from a web browser. These tools also allow for Java to be used in a large variety of applications, making the Java programming language very popular and widely used!

The Java Platform Today

Today, Java is used commonly across many industries and is known as a high-level, general-purpose programming language.

lines of code in Java

An example of lines of code in Java, from a Java project. Because Java is a high-level language, some of the words used are similar to normal English!

  • High-level means that a language is relatively similar to human languages in how its written, and is thus easier for human programmer intuitively understand and interpret.
  • General-purpose languages in computer science refer to coding languages that can be used to build solutions for a variety of problems, opposed to being limited to a specific industry or problem type.

As a result, the Java platform is extremely popular today for a wide range of uses — being the most used development platform, and the number one choice for developers.

It is also one of the most frequently taught coding languages, and is suitable for coders ages 12+ to learn.

What is Java Used For?


According to Oracle, more than 3 billion devices run Java, and most major companies use Java in one way or another. Java is used in a large number of fields, from scientific applications like physics simulators, to financial applications like e-commerce websites.

Major companies like Google, Microsoft and many others also use Java for a number of purposes.

Check out some of the major applications of Java below.

Web Development

  • Although HTML and Javascript are commonly used to write websites and other web applications, Java has a number of packages and libraries that are useful for web development.
  • Java is also well-suited to server-side web development, that is, programs that interact directly with the server (a type of device that provides some functionality, like managing resources, to client devices).


  • Google Android apps, and the Android operating system as well, are written using Java, and the Google Android API, which is very similar to the Java Development Kit (JDK).
  • While Android applications use a different JVM, the code is still written in Java.
Google Android phone system built using Java

The Google Android operating system is built using Java code.

Finance and E-Commerce

  • Many e-commerce websites, as well as government, healthcare, insurance, education and defense web applications are built in Java, making Java programmers valuable in a large host of industries.
  • Java’s implementation makes it a secure language, which is important for e-commerce websites that handle large amounts of secure data like credit card numbers and users’ addresses.
  • There are a number of features in Java that make it a secure programming language.
  • For example, Java confines a Java application to the Java execution environment, and doesn’t let it access system resources, which helps prevent a security breach.

Big Data

  • Big Data technologies, which have been gaining tremendous momentum, are also commonly written in Java.
  • Java is the preferred choice for the relatively new field of Big Data because of its large, well-curated open source libraries, as well as a large community of experienced Java programmers.
  • Java also has a number of packages that are useful for data processing and scientific computing, both of which make it well-suited to data science applications.


  • Games and game AIs are also written in Java.
  • Popular games like Minecraft are built using Java too!
  • Games use core Java concepts like OOP (object oriented programming) and multithreading. Multithreading is the simultaneous execution of two or more processes, with the most efficient use of the CPU.
Minecraft game built using Java

Even popular games like Minecraft are built with Java coding!

Pros and Cons of Java

Just like all coding languages, Java also has its own unique strengths and weaknesses. When programmers decide what language to use for a program or project, they must consider the limitations of each coding language as well as the unique advantages each may offer.

If you’re considering using or learning Java, check out some of its pros and cons listed below.


SimpleJava is easy to learn and use, since it was created to be more straightforward to write, compile and debug than alternative programming languages at the time of its creation, like C++.
Versatile and PowerfulThe strength of Java programming comes from its various components. The Java Development Kit (JDK), Java Virtual Machine (JVM) and the Java Runtime Environment (JRE) form the trifecta of Java platform components for developing and running Java applications.
The JRE, or more specifically, the Java SE (Standard Edition) Runtime Environment, is a piece of software that is designed to run code written in Java. The JRE contains the JVM, and the Java class libraries, which are essential to running Java code. The JDK allows programmers to create Java programs that can be executed and run by the JVM and JRE.
Object-Oriented ProgrammingObject-oriented programming languages are good for writing modular and reusable code.
Platform-IndependentJava code runs on any machine that has JVM on it, without needing any special software.
This allows Java developers to create “write once, run anywhere” programs, which make collaboration and distribution of ideas and applications easier. This is also crucial for World Wide Web software, which needs to be able to run on any operating system, from Windows to macOS to Linux.
SecurityJava’s implementation and compilation details make it well-suited to applications where security is important.
Easy to LearnJava was created to be easy to understand, learn, and use for coders of various ages. It has simpler syntax than languages like C and C++, and requires no knowledge of memory systems or other low-level computing details!


PerformanceCompared to natively compiled languages like C and C++, Java is memory-consuming and slow.
Memory ManagementIn Java, memory is managed through a garbage collector, which handles reclaiming memory occupied by unused data. This garbage collection method in Java affects performance of the application.
SyntaxAlthough Java is a high level programming language, its syntax can still come with a learning curve. While easier than programming languages like C++, Java has more specific and less intuitive syntax than languages like Python or Scratch.

Want to Start Learning Java?

As we discussed above, one of Java’s greatest strengths is being easy to learn and a great introductory language for newer and intermediate coders.

With its wide applications, learning Java programming also opens the door to a number of potential careers, from app developer or web developer, to data analyst or server-side software engineer!

With a large online developer community, there are a number of online resources for learning about more specific APIs and tools related to Java. New coders can also easily search up their answers to common Java issues or questions they may run into.

Online Java Classes for Kids

A Juni instructor teaching Python.

A Juni Instructor teaches basic coding in Python to a young student.

For students who want more structured learning, Juni Learning teaches a sequence of Java courses — starting with the basics, leading up to more complicated projects using objects and subclasses. These courses teach students programming concepts in the Java language through hands-on projects.

Java is great for kids 12+, especially those who have prior knowledge of coding or Python coding. For younger students 8-11, we highly recommend starting with Scratch to help introduce computer programming concepts without being slowed down by difficult syntax.

Read more about our coding courses and curriculum, or enroll for classes with our Admissions Team to learn which course is best for your student’s coding journey.

This article originally appeared on junilearning.com.